WO2021241571A1

WO2021241571A1 - Layered product including high temperature-resistant transparent film

Info

Publication number: WO2021241571A1
Application number: PCT/JP2021/019787
Authority: WO
Inventors: 哲雄奧山; 誠中村; 伝一朗水口; 治美米虫; 洋行涌井; 桂也 ▲徳▼田
Original assignee: 東洋紡株式会社
Priority date: 2020-05-29
Filing date: 2021-05-25
Publication date: 2021-12-02
Also published as: JPWO2021241571A1; KR20220165774A; CN115551714A; EP4159440A1; US20230211584A1; TW202144175A

Abstract

Provided is a layered product that uses a high temperature-resistant transparent film having sufficient heat resistance, and that is capable of being mechanically released from an inorganic substrate after various processes are performed on the inorganic substrate since the adhesive strength between the high temperature-resistant transparent film and the inorganic substrate is appropriately weak, and that is less warped along with the inorganic substrate.　In this layered product, no adhesive is used between the high temperature-resistant transparent film and the inorganic substrate, the release strength between the high temperature-resistant transparent film and the inorganic substrate is at most 0.3 N/cm, and the warpage amount of the layered product when heated at 300°C is at most 400 μm.

Description

Laminated body containing transparent high heat resistant film

The present invention relates to a laminate containing a highly heat resistant film.

In recent years, there has been an increasing demand for seats with multiple devices mounted at intervals, which have both flexibility and elasticity. Such a sheet is supposed to be used by being attached to a curved surface such as a body, for example. Further, it is expected to be used for an electronic device having a bent portion and an electronic device that can be wound. If these sheets are transparent, various uses are promising mainly for display applications, and they are being actively studied.

Patent Document 1 describes a polyimide film for a supporting base material that can be made thin, lightweight, and flexible, has no problems of cracking or peeling due to thermal stress, and is used for manufacturing an organic EL device having excellent dimensional stability and the like. Is disclosed. A polyimide or a resin solution of a polyimide precursor is applied onto the base substrate so that the thickness of the polyimide film is 50 μm or less, the heat treatment is completed to form the polyimide film on the base substrate, and the polyimide film is formed from the base substrate. A method for manufacturing a polyimide film for a display device support base material, which has a transmittance of 80% or more in the wavelength region of 440 nm to 780 nm and a transmittance of 80% or less at 400 nm. There is a method of producing a polyimide film for a display device support base material by irradiating the bottom surface of the polyimide film with laser light through the base substrate in order to separate the polyimide film and the base substrate.

Further, Patent Document 2 describes a polyimide film, a glass plate, and a ceramic plate having a higher level of heat resistance and flexibility as a laminate having a silane coupling layer between an inorganic layer and a polyimide film layer. A laminate with excellent heat resistance and insulation, in which a silicon wafer and a kind of inorganic layer selected from metal are laminated, is extremely significant when used for making electronic devices, optical functional components, electronic components, etc. There is.

Japanese Unexamined Patent Publication No. 2018-132768 Patent No. 5304490

However, in the circuit board manufacturing method as described in Patent Document 1, it is necessary to irradiate the entire bottom surface of the polyimide film with laser light through the base substrate, which is inferior in productivity. In particular, when the area is large, high precision is required for laser processing, which is not suitable for mass production. In addition, since smears are generated during laser processing, these smears become particles and cause damage to the device or break the wiring. Further, the laminate described in Patent Document 2 has a strong 180-degree peel strength between the inorganic layer and the polyimide film of 1 N / cm or more, and a device is formed on the polyimide film layer, and then the device-formed polyimide film is machined. It was difficult to peel it off.

The present invention has been made in view of the above-mentioned problems, and an object thereof is that after forming a device on a transparent high heat resistant film, it is very easy to separate the transparent high heat resistant film from the inorganic substrate. It is an object of the present invention to provide a method for manufacturing a device conjugate, which is easy to manufacture a film with an electronic device and can be mass-produced. The present invention also provides a laminate of a transparent high heat resistant film and an inorganic substrate for manufacturing the device.

The present inventors have diligently studied the manufacture of devices on transparent high heat resistant films. As a result, they have found that if the following components are adopted, the device on the transparent high heat resistant film can be easily manufactured and mass-produced, and the present invention has been completed. That is, the laminated body according to the present invention has the following structure.

In a laminate that substantially does not use an adhesive between a transparent high heat resistant film and an inorganic substrate,
A laminate in which the peel strength between the transparent high heat resistant film and the inorganic substrate is 0.3 N / cm or less, and the amount of warpage of the laminate when heated at 300 ° C. is 400 μm or less.

The transparent high heat resistant film has a laminated structure of two or more layers, and is adjacent to the first transparent high heat resistant film layer that comes into contact with the inorganic substrate and the first transparent high heat resistant film layer that does not come into contact with the inorganic substrate. It is preferable that the thickness of the mixture with the second transparent high heat resistant film layer is more than 800 nm and 5 μm or less.

It is preferable that the transparent high heat resistant film has a laminated structure of two or more layers, and the CTE of the first transparent high heat resistant film layer alone in contact with the inorganic substrate is 20 ppm / K or less.

It is preferable that the transparent high heat resistant film has a laminated structure of two or more layers, and the first transparent high heat resistant film layer in contact with the inorganic substrate is transparent polyimide.

It is preferable that the transparent high heat resistant film has a laminated structure of two or more layers, and at least one layer of the second transparent high heat resistant film layer that does not come into contact with the inorganic substrate is transparent polyimide.

It is preferable that the transparent high heat resistant film has a laminated structure of two or more layers, and the first transparent high heat resistant film layer in contact with the inorganic substrate contains the structure of the formula 1 and / or the structure of the formula 2.

It is preferable that the long side of the inorganic substrate is 300 mm or more.

A method for manufacturing a film with an electronic device, in which an electronic device is formed on the transparent high heat resistant film of the laminated body and then peeled off from an inorganic substrate.

According to the present invention, since it is very easy to peel off the transparent high heat resistant film and the inorganic substrate after forming the device, it is easy to manufacture a film with an electronic device, and a method for manufacturing a device conjugate capable of mass production. Can be provided. Further, it is possible to provide a laminate of the transparent high heat resistant film and an inorganic substrate, and the laminate has a small amount of warpage during heating.

It is a schematic diagram for demonstrating the silane coupling agent application method which concerns on this patent. It is a schematic cross-sectional view example for demonstrating the manufacturing method of the film with an electronic device which concerns on this patent. It is another schematic cross-sectional view example for demonstrating the manufacturing method of the film with an electronic device which concerns on this patent. It is a schematic cross-sectional view example for demonstrating the measurement of the warp of the laminated body of a transparent high heat resistant film and an inorganic substrate which concerns on this patent.

Hereinafter, embodiments of the present invention will be described.

<Transparent high heat resistant film>
In the present specification, the transparent high heat resistant film is preferably a film having a melting point of 250 ° C. or higher, more preferably 300 ° C. or higher, and further preferably 400 ° C. or higher. Further, the glass transition temperature is preferably 200 ° C. or higher, more preferably 320 ° C. or higher, and further preferably 380 ° C. or higher. Hereinafter, it is also simply referred to as a polymer in order to avoid complication. In the present specification, the melting point and the glass transition temperature are determined by differential thermal analysis (DSC). When the melting point exceeds 500 ° C., it may be determined whether or not the melting point has been reached by visually observing the thermal deformation behavior when heated at the corresponding temperature.

Further, as the transparency, it is preferable that the total light transmittance is 75% or more. It is more preferably 80% or more, further preferably 85% or more, further preferably 87% or more, and particularly preferably 88% or more. The upper limit of the total light transmittance of the transparent high heat resistant film is not particularly limited, but is preferably 98% or less, more preferably 97 for use as a film with an electronic device (hereinafter, also referred to as a flexible electronic device). % Or less.

The transparent high heat resistant film (hereinafter, also simply referred to as a polymer film) includes polyimide resins such as polyimide, polyamideimide, polyetherimide, and fluorinated polyimide (for example, aromatic polyimide resin and alicyclic polyimide resin); polyethylene. , Polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate and other copolymerized polyesters (eg, fully aromatic polyesters, semi-aromatic polyesters); copolymerized (meth) acrylates typified by polymethylmethacrylate; polycarbonate. Polyimide; Polysulphon; Polyethersulphon; Polyetherketone; Cellulose acetate; Cellulite nitrate; Aromatic polyamide; Polyvinyl chloride; Polyphenol; Polyallylate; Polyacetal; Modified polyphenylene ether; Polyphenylene sulfide; Polyphenylene oxide; Polystyrene; Polybenzoxazole Examples thereof include films such as polybenzothiazole; polybenzoimidazole; cyclic polyimide; and liquid crystal polymers. Further, examples thereof include those reinforced with glass filler, glass fiber and the like.
However, since the polymer film is premised on being used in a process involving a heat treatment of 250 ° C. or higher, the polymer films exemplified are limited to those that can be actually applied. Among the polymer films, a film using a so-called super engineering plastic is preferable, and more specifically, an aromatic polyimide film, an alicyclic polyimide film, an aromatic amide film, an aromatic amide imide film, and an amide. Examples thereof include imide film, aromatic benzoxazole film, aromatic benzothiazole film, aromatic benzoimidazole film, cyclic polyolefin, liquid crystal polymer and the like.

The details of the polyimide resin film (sometimes referred to as a polyimide film), which is an example of the polymer film, will be described below. Generally, a polyimide-based resin film is a green film (hereinafter referred to as a green film) in which a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent is applied to a support for producing a polyimide film and dried. (Also referred to as "precursor film" or "polyamic acid film"), and further, the green film is heat-treated at high temperature on a support for producing a polyimide film or in a state of being peeled off from the support to carry out a dehydration ring closure reaction. can get. Here, the green film is a polyamic acid film containing a solvent and having self-supporting properties. The solvent content of the green film is not particularly limited as long as it has self-supporting property, but is preferably 1% by mass or more, more preferably 5% by mass or more, and further preferably 10% by mass or more. Yes, more preferably 20% by mass or more, and particularly preferably 30% by mass or more. Further, it is preferably 80% by mass or less, more preferably 70% by mass or less, further preferably 60% by mass or less, and particularly preferably 50% by mass or less.

The application of the polyamic acid (polyimide precursor) solution is, for example, application of a conventionally known solution such as spin coating, doctor blade, applicator, comma coater, screen printing method, slit coating, reverse coating, dip coating, curtain coating, and slit die coating. Means can be used as appropriate. Since the method of applying a polyamic acid solution to form a film has a wide range of material selections, it is easy to study in order to find a material preferable for easy peeling, but it is necessary to control the imidization reaction. On the other hand, a film-forming film that does not involve an imidization reaction has an advantage that it is easy to form a film, so it is necessary to use them properly.

The polyimide film in the present invention is a polymer film having an imide bond in the main chain, preferably a polyimide film or a polyamide-imide film, and more preferably a polyimide film. A polyamide film is also preferable.

Generally, as described above, a polyimide film is green by applying a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent to a support for producing a polyimide film and drying it. It is obtained by subjecting a green film to a high-temperature heat treatment on a support for producing a polyimide film or in a state of being peeled off from the support to carry out a dehydration ring closure reaction. As another method, a polyimide solution obtained by a dehydration ring closure reaction between diamines and tetracarboxylic acids in a solvent is applied to a support for producing a polyimide film, dried, and contains, for example, 1 to 50% by mass of a solvent. It can also be obtained by treating a polyimide film containing a solvent of 1 to 50% by mass at a high temperature and drying it on a support for producing a polyimide film or in a state of being peeled off from the support.

Further, in general, a polyamide-imide film is prepared by applying a polyamide-imide solution obtained by reacting diisocyanates and tricarboxylics in a solvent to a support for producing a polyamide-imide film and drying the mixture, for example, by mass of 1 to 50 mass. The polyamide-imide film containing 1 to 50% by mass of the solvent is treated at a high temperature and dried on the support for producing the polyamide-imide or in a state of being peeled off from the support. Obtained at.

Further, in general, a polyamide film contains a polyamide solution obtained by reacting diamines and dicarboxylic acids in a solvent, applied to a support for producing a polyamide film, dried, and contained, for example, 1 to 50% by mass of a solvent. It is obtained by treating a polyamide film containing a solvent of 1 to 50% by mass at a high temperature and drying it on a support for producing a polyamide or in a state of being peeled off from the support.

Examples of the tetracarboxylic acids, tricarboxylic acids and dicarboxylic acids include aromatic tetracarboxylic acids (including acid anhydrides thereof) and aliphatic tetracarboxylic acids (acid anhydrides thereof) usually used for polyimide synthesis, polyamideimide synthesis and polyamide synthesis. (Including), alicyclic tetracarboxylic acids (including its acid anhydride), aromatic tricarboxylic acids (including its acid anhydride), aliphatic tricarboxylic acids (including its acid anhydride), alicyclic tricarboxylic acids. (Including the acid anhydride thereof), aromatic dicarboxylic acids, aliphatic dicarboxylic acids, alicyclic dicarboxylic acids and the like can be used. Among them, aromatic tetracarboxylic acid anhydrides and aliphatic tetracarboxylic acid anhydrides are preferable, aromatic tetracarboxylic acid anhydrides are more preferable from the viewpoint of heat resistance, and alicyclic type from the viewpoint of light transmission. Tetracarboxylic acids are more preferred. When the tetracarboxylic acids are acid anhydrides, the number of anhydride structures in the molecule may be one or two, but those having two anhydride structures (dianhydride) are preferable. ) Is good. Tetracarboxylic acids, tricarboxylic acids, and dicarboxylic acids may be used alone or in combination of two or more.

Examples of the aromatic tetracarboxylic acids for obtaining a highly colorless and transparent polyimide in the present invention include 4,4'-(2,2-hexafluoroisopropyridene) diphthalic acid, 4,4'-oxydiphthalic acid, and bis (1). , 3-Dioxo-1,3-dihydro-2-benzofuran-5-carboxylic acid) 1,4-phenylene, bis (1,3-dioxo-1,3-dihydro-2-benzofuran-5-yl) benzene- 1,4-dicarboxylate, 4,4'-[4,4'-(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl) bis (benzene-1,4-diyloxy) ] Dibenzene-1,2-dicarboxylic acid, 3,3', 4,4'-benzophenonetetracarboxylic acid, 4,4'-[(3-oxo-1,3-dihydro-2-benzofuran-1,1-) Diyl) bis (toluene-2,5-diyloxy)] dibenzene-1,2-dicarboxylic acid, 4,4'-[(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl) bis (1,4-Xylene-2,5-diyloxy)] Dibenzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3-oxo-1,3-dihydro-2-benzofuran-1) , 1-diyl) bis (4-isopropyl-toluene-2,5-diyloxy)] dibenzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3-oxo-1,3-dihydro) -2-benzofuran-1,1-diyl) bis (naphthalen-1,4-diyloxy)] dibenzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benz) Oxathiol-1,1-dioxide-3,3-diyl) bis (benzene-1,4-diyloxy)] dibenzene-1,2-dicarboxylic acid, 4,4'-benzophenonetetracarboxylic acid, 4,4'- [(3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl) bis (toluene-2,5-diyloxy)] dibenzene-1,2-dicarboxylic acid, 4,4'-[ (3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl) Bis (1,4-xylene-2,5-diyloxy)] Dibenzene-1,2-dicarboxylic acid, 4,4 '-[4,4'-(3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl) bis (4-isopropyl-toluene-2,5-diyloxy)] dibenzene-1, 2-Dicarboxylic acid, 4,4'-[4,4' -(3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl) bis (naphthalen-1,4-diyloxy)] dibenzene-1,2-dicarboxylic acid, 3,3', 4 , 4'-benzophenone tetracarboxylic acid, 3,3', 4,4'-benzophenone tetracarboxylic acid, 3,3', 4,4'-diphenylsulfone tetracarboxylic acid, 3,3', 4,4'- Biphenyltetracarboxylic acid, 2,3,3', 4'-biphenyltetracarboxylic acid, 2,2', 3,3'-biphenyltetracarboxylic acid, 2,2'-diphenoxy-4,4', 5,5 '-Biphenyltetracarboxylic acid, pyromellitic acid, 4,4'-[Spiro (xanthene-9,9'-fluorene) -2,6-diylbis (oxycarbonyl)] diphthalic acid, 4,4'-[Spiro ( Examples thereof include tetracarboxylic acids such as xanthene-9,9'-fluorene) -3,6-diylbis (oxycarbonyl)] diphthalic acid, and acid anhydrides thereof. Among these, a dianhydride having two acid anhydride structures is preferable, and in particular, 4,4'-(2,2-hexafluoroisopropylidene) diphthalic acid dianhydride and 4,4'-oxydiphthal. Acid dianhydride is preferred. The aromatic tetracarboxylic acids may be used alone or in combination of two or more. The copolymerization amount of the aromatic tetracarboxylic acids is preferably, for example, 50% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass, when heat resistance is important. The above is more preferably 80% by mass or more.

Examples of the alicyclic tetracarboxylic acids include 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,3,4-cyclohexanetetracarboxylic acid, and 1 , 2,4,5-Cyclohexanetetracarboxylic acid, 3,3', 4,4'-bicyclohexyltetracarboxylic acid, bicyclo [2,2,1] heptane-2,3,5,6-tetracarboxylic acid, Bicyclo [2,2,2] octane-2,3,5,6-tetracarboxylic acid, bicyclo [2,2,2] octo-7-en-2,3,5,6-tetracarboxylic acid, tetrahydroanthracene -2,3,6,7-tetracarboxylic acid, tetradecahydro-1,4: 5,8: 9,10-trimethanoanthracene-2,3,6,7-tetracarboxylic acid, decahydronaphthalene-2 , 3,6,7-Tetracarboxylic Acid, Decahydro-1,4: 5,8-Dimethanonaphthalene-2,3,6,7-Tetracarboxylic Acid, Decahydro-1,4-Etano-5,8-Metano Naphthalene-2,3,6,7-tetracarboxylic acid, norbornan-2-spiro-α-cyclopentanone-α'-spiro-2''-norbornan-5,5'', 6,6''-tetra Carboxylic acid (also known as "norbornan-2-spiri-2'-cyclopentanone-5'-spiro-2"-norbornan-5,5 ", 6,6" -tetracarboxylic acid "), methylnorbornan- 2-Spiro-α-Cyclopentanone-α'-Spiro-2''-(methylnorbornan) -5,5'', 6,6''-tetracarboxylic acid, norbornan-2-spiro-α-cyclohexanone- α'-Spiro-2''-norbornan-5,5'', 6,6''-tetracarboxylic acid (also known as "norbornan-2-spiriro-2'-cyclohexanone-6'-spiro-2"-norbornan -5,5'', 6,6''-tetracarboxylic acid "), Methylnorbornan-2-spiro-α-cyclohexanone-α'-spiro-2''- (methylnorbornan) -5,5'', 6,6''-tetracarboxylic acid, norbornan-2-spiro-α-cyclopropanol-α'-spiro-2''-norbornan-5,5'', 6,6''-tetracarboxylic acid, norbornan -2-Spiro-α-Cyclobutanone-α'-Spiro-2''-norbornan-5,5'', 6,6''-tetracarboxylic acid, norbornan-2-spiro-α-cycloheptanone-α'-Spiro-2''-Norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclooctanone-α'-spiro-2''-norbornane-5,5'', 6 , 6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclononanon-α'-spiro-2''-norbornane-5,5'', 6,6''-tetracarboxylic acid, norbornane-2- Spiro-α-cyclodecanone-α'-spiro-2''-norbornane-5,5'', 6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cycloundecanone-α'-spiro- 2''-norbornane-5,5'', 6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclododecanone-α'-spiro-2''-norbornane-5,5'' , 6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclotridecanone-α'-spiro-2''-norbornane-5,5'', 6,6''-
Tetracarboxylic acid, norbornane-2-spiro-α-cyclotetradecanone-α'-spiro-2''-norbornane-5,5'', 6,6''-tetracarboxylic acid, norbornane-2-spiro- α-Cyclopentadecanone-α'-Spiro-2''-norbornane-5,5'', 6,6''-tetracarboxylic acid, norbornane-2-spiro-α- (methylcyclopentanone) -α '-Spyro-2''-Norbornane-5,5'', 6,6''-Tetracarboxylic acid, Norbornane-2-Spyro-α- (methylcyclohexanone) -α'-Norbornane-2''-Norbornane- Examples thereof include tetracarboxylic acids such as 5,5'', 6,6''-tetracarboxylic acid, and their acid anhydrides. Among these, dianhydride having two acid anhydride structures is preferable, and in particular, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-cyclohexanetetracarboxylic. Acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride is preferred, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic Acid dianhydride is more preferred, and 1,2,3,4-cyclobutanetetracarboxylic hydride is even more preferred. These may be used alone or in combination of two or more. The copolymerization amount of the alicyclic tetracarboxylic acids is preferably, for example, 50% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass, when transparency is important. % Or more, and even more preferably 80% by mass or more.

Examples of tricarboxylic acids include aromatic tricarboxylic acids such as trimellitic acid, 1,2,5-naphthalene tricarboxylic acid, diphenyl ether-3,3', 4'-tricarboxylic acid, and diphenylsulfone-3,3', 4'-tricarboxylic acid. An acid or an alkylene such as a hydrogenated additive of the above aromatic tricarboxylic acid such as hexahydrotrimellitic acid, ethylene glycol bistrimerite, propylene glycol bistrimerite, 1,4-butanediol bistrimerite, polyethylene glycol bistrimerite. Glycolbitrimeritate and these monoanhydrides and esterified products can be mentioned. Among these, monoanhydride having one acid anhydride structure is preferable, and in particular, trimellitic acid anhydride and hexahydrotrimellitic acid anhydride are preferable. These may be used alone or in combination of two or more.

Examples of the dicarboxylic acids include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, 4,4'-oxydibenzenecarboxylic acid, and the above aromatic dicarboxylic acid such as 1,6-cyclohexanedicarboxylic acid. Hydrogen additives, oxalic acid, succinic acid, glutaric acid, adipic acid, heptanedioic acid, octanedioic acid, azelaioic acid, sebacic acid, undecadioic acid, dodecanedioic acid, 2-methylsuccinic acid, and their acid salts. Alternatively, an esterified product or the like can be mentioned. Among these, aromatic dicarboxylic acids and hydrogen additives thereof are preferable, and terephthalic acid, 1,6-cyclohexanedicarboxylic acid, 4,4'-oxydibenzenecarboxylic acid are particularly preferable. The dicarboxylic acids may be used alone or in combination of two or more.

The diamines or isocyanates for obtaining a polyimide having high colorless transparency in the present invention are not particularly limited, and are aromatic diamines, aliphatic diamines, and fats usually used for polyimide synthesis, polyamide-imide synthesis, and polyamide synthesis. Cyclic diamines, aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates and the like can be used. From the viewpoint of heat resistance, aromatic diamines are preferable, and from the viewpoint of transparency, alicyclic diamines are preferable. Further, when aromatic diamines having a benzoxazole structure are used, it is possible to exhibit high elastic modulus, low coefficient of thermal expansion, and low linear expansion coefficient as well as high heat resistance. Diamines and isocyanates may be used alone or in combination of two or more.

Examples of aromatic diamines include 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,4-bis [2- (4-aminophenyl) -2-propyl] benzene, and 1,4-bis. (4-Amino-2-trifluoromethylphenoxy) benzene, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'- Bis (3-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone , 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoro Propane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 4-amino-N- (4-aminophenyl) benzamide, 3,3'-diaminodiphenyl ether , 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2'-trifluoromethyl-4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenylsulfide, 3,4'-diaminodiphenyl Sulfur, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, 3,3'-diaminodiphenyl sulfone, 3,4 '-Diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4 '-Diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis [4- (4-aminophenoxy) phenyl] methane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-Aminophenoxy) phenyl] ethane, 1,1-bis [4- (4-aminophenoxy) phenyl] propane, 1,2-bis [4- (4-aminophenoxy) phenyl] propane, 1 , 3-Bis [4- (4-aminophenoxy) phenyl] propane, 2,2 -Bis [4- (4-aminophenoxy) phenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] butane, 1,3-bis [4- (4-aminophenoxy) phenyl] butane , 1,4-bis [4- (4-aminophenoxy) phenyl] butane, 2,2-bis [4- (4-aminophenoxy) phenyl] butane, 2,3-bis [4- (4-aminophenoxy) ) Phenyl] butane, 2- [4- (4-aminophenoxy) phenyl] -2- [4- (4-aminophenoxy) -3-methylphenyl] propane, 2,2-bis [4- (4-amino) Phenoxy) -3-methylphenyl] propane, 2- [4- (4-aminophenoxy) phenyl] -2- [4- (4-aminophenoxy) -3,5-dimethylphenyl] propane, 2,2-bis [4- (4-Aminophenoxy) -3,5-dimethylphenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoro Propane, 1,4-bis (3-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-) Aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfoxide, bis [4 -(4-Aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether, 1,3-bis [4- (4- (4-) Aminophenoxy) benzoyl] benzene, 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene, 1,4-bis [4- (3-aminophenoxy) benzoyl] benzene, 4,4'-bis [ (3-Aminophenoxy) benzoyl] benzene, 1,1-bis [4- (3-aminophenoxy) phenyl] propane, 1,3-bis [4- (3-aminophenoxy) phenyl] propane, 3,4' -Diaminodiphenyl sulfide, 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, bis [4- (3-aminophenoxy) phenyl] Methan, 1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2-bi Su [4- (3-aminophenoxy) phenyl] ethane, bis [4- (3-aminophenoxy) phenyl] sulfoxide, 4,4'-bis [3- (4-aminophenoxy) benzoyl] diphenyl ether, 4,4 '-Bis [3- (3-aminophenoxy) benzoyl] diphenyl ether, 4,4'-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzophenone, 4,4'-bis [4- (4-Amino-α, α-dimethylbenzyl) phenoxy] diphenyl sulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone, 1,4-bis [4- (4-aminophenoxy) Phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6) -Trifluoromethylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-fluorophenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [ 4- (4-Amino-6-methylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-cyanophenoxy) -α, α-dimethylbenzyl] benzene, 3,3'-diamino-4,4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-diphenoxybenzophenone, 3,4'-diamino-4,5'-diphenoxybenzophenone, 3, 3'-Diamino-4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3,4'-diamino-5'-phenoxybenzophenone, 3,3 '-Diamino-4,4'-dibiphenoxybenzophenone, 4,4'-diamino-5,5'-dibiphenoxybenzophenone, 3,4'-diamino-4,5'-dibiphenoxybenzophenone, 3,3'- Diamino-4-biphenoxybenzophenone, 4,4'-diamino-5-biphenoxybenzophenone, 3,4'-diamino-4-biphenoxybenzophenone, 3,4'-diamino-5'-biphenoxybenzophenone, 1, 3-Bis (3-amino-4-phenoxybenzoyl) benzene, 1,4-bis (3-amino-4-phenoxybenzoyl) benzene, 1,3-bis (4-amino-5-phenoyl) Xybenzoyl) benzene, 1,4-bis (4-amino-5-phenoxybenzoyl) benzene, 1,3-bis (3-amino-4-biphenoxybenzoyl) benzene, 1,4-bis (3-amino-) 4-Bifenoxybenzoyl) benzene, 1,3-bis (4-amino-5-biphenoxybenzoyl) benzene, 1,4-bis (4-amino-5-biphenoxybenzoyl) benzene, 2,6-bis [ 4- (4-Amino-α, α-dimethylbenzyl) phenoxy] benzonitrile, 4,4'-[9H-fluorene-9,9-diyl] bisaniline (also known as "9,9-bis (4-aminophenyl)) Fluorene "), Spiro (xanthene-9,9'-fluorene) -2,6-diylbis (oxycarbonyl)] bisaniline, 4,4'-[spiro (xanthen-9,9'-fluorene) -2,6- Examples thereof include diylbis (oxycarbonyl)] bisaniline, 4,4'-[spiro (xanthene-9,9'-fluorene) -3,6-diylbis (oxycarbonyl)] bisaniline and the like. Further, a part or all of the hydrogen atoms on the aromatic ring of the aromatic diamine may be substituted with a halogen atom, an alkyl group or an alkoxyl group having 1 to 3 carbon atoms, or a cyano group, and further, the carbon number 1 may be substituted. A part or all of the hydrogen atom of the alkyl group or the alkoxyl group of ~ 3 may be substituted with a halogen atom. The aromatic diamine having the benzoxazole structure is not particularly limited, and for example, 5-amino-2- (p-aminophenyl) benzoxazole and 6-amino-2- (p-aminophenyl) benzo. Oxazole, 5-amino-2- (m-aminophenyl) benzoxazole, 6-amino-2- (m-aminophenyl) benzoxazole, 2,2'-p-phenylenebis (5-aminobenzoxazole), 2 , 2'-p-phenylenebis (6-aminobenzoxazole), 1- (5-aminobenzoxazole) -4- (6-aminobenzoxazolo) benzene, 2,6- (4,4'-diamino Diphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (4,4-diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole , 2,6- (3,4'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (3,4'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] -D: 4,5-d'] bisoxazole, 2,6- (3,3'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (3) , 3'-diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole and the like. Among these, in particular, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 4-amino-N- (4-aminophenyl) benzamide, 4,4'-diaminodiphenyl sulfone, 3,3 '-Diaminobenzophenone is preferred. The aromatic diamines may be used alone or in combination of two or more.

Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-2-ethylcyclohexane, and 1,4-diamino-2-n-propyl. Cyclohexane, 1,4-diamino-2-isopropylcyclohexane, 1,4-diamino-2-n-butylcyclohexane, 1,4-diamino-2-isobutylcyclohexane, 1,4-diamino-2-sec-butylcyclohexane, Examples thereof include 1,4-diamino-2-tert-butylcyclohexane and 4,4'-methylenebis (2,6-dimethylcyclohexylamine). Among these, 1,4-diaminocyclohexane and 1,4-diamino-2-methylcyclohexane are particularly preferable, and 1,4-diaminocyclohexane is more preferable. The alicyclic diamines may be used alone or in combination of two or more.

Examples of diisocyanates include diphenylmethane-2,4'-diisocyanate, 3,2'-or 3,3'-or 4,2'-or 4,3'-or 5,2'-or 5,3'. -Or 6,2'-or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'-or 3,3'-or 4,2'-or 4,3'-or 5,2 '-Or 5,3'-or 6,2'-or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3,2'-or 3,3'-or 4,2'-or 4, 3'-or 5,2'-or 5,3'-or 6,2'-or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-3, 3'-diisocyanate, diphenylmethane-3,4'-diisocyanate, diphenylether-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, diphenylsulfone-4,4'-diisocyanate, tolylen-2,4-diisocyanate, Trilen-2,6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanis, 4,4'-(2,2 bis (4-phenoxyphenyl) propane) diisocyanate, 3, 3'-or 2,2'-dimethylbiphenyl-4,4'-diisocyanate, 3,3'-or 2,2'-diethylbiphenyl-4,4'-diisocyanis, 3,3'-dimethoxybiphenyl-4, Aromatic diisocyanes such as 4'-diisethylene, 3,3'-diethoxybiphenyl-4,4'-diisocyanis, and diisocyanates obtained by hydrogenating any of these (for example, isophorone diisocyanate, 1,4-cyclohexanediisocyanis, etc.) 1,3-Cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate) and the like. Among these, diphenylmethane-4,4'-diisocyanate, tolylen-2,4-diisocyanate, tolylen-2,6-diisocyanate, 3,3'-in terms of low hygroscopicity, dimensional stability, price and polymerizability. Dimethylbiphenyl-4,4'-diisocyanate, naphthalene-2,6-diisocyanate, 4,4'-dicyclohexylmethanediisocyanate and 1,4-cyclohexanediisocyanate are preferable. The diisocyanates may be used alone or in combination of two or more.

The transparent high heat-resistant film of the present invention may have a single-layer structure or a laminated structure of two or more layers. From the viewpoint of the physical strength of the transparent high heat-resistant film and the ease of peeling from the inorganic substrate, it is preferable to have a laminated structure of two or more layers, and a laminated structure of three or more layers may be used. note that,
In the present specification, the physical characteristics (yellowness index, total light transmittance, haze, etc.) when the transparent high heat resistant film has two or more layers are the values of the entire transparent high heat resistant film unless otherwise specified. ..

The yellowness index (hereinafter, also referred to as “yellow index” or “YI”) of the transparent high heat resistant film in the present invention is preferably 10 or less, more preferably 7 or less, still more preferably 5 or less, and further. It is preferably 3 or less. The lower limit of the yellowness index of the transparent high heat resistant film is not particularly limited, but is preferably 0.1 or more, more preferably 0.2 or more, and further preferably 0. 3 or more.

The light transmittance of the transparent high heat resistant film in the present invention at a wavelength of 400 nm is preferably 70% or more, more preferably 72% or more, further preferably 75% or more, still more preferably 80% or more. The upper limit of the light transmittance of the transparent high heat resistant film at a wavelength of 400 nm is not particularly limited, but is preferably 99% or less, more preferably 98% or less, still more preferably 97 for use as a flexible electronic device. % Or less.

The total light transmittance of the transparent high heat resistant film in the present invention is preferably 75% or more, more preferably 85% or more, further preferably 87% or more, and even more preferably 88% or more. The upper limit of the total light transmittance of the transparent high heat resistant film is not particularly limited, but is preferably 98% or less, more preferably 97% or less for use as a flexible electronic device.

The haze of the transparent high heat resistant film in the present invention is preferably 1.0 or less, more preferably 0.8 or less, still more preferably 0.5 or less, and even more preferably 0.3 or less.

The thickness direction retardation (Rth) of the transparent high heat resistant film in the present invention is preferably 500 nm or less, more preferably 300 nm or less, still more preferably 200 nm or less, and even more preferably 100 nm or less. The lower limit of Rth of the transparent high heat resistant film is not particularly limited, but is preferably 0.1 nm or more, and more preferably 0.5 nm or more for use as a flexible electronic device.

The thickness of the transparent high heat resistant film in the present invention is preferably 5 μm or more, more preferably 8 μm or more, further preferably 15 μm or more, and even more preferably 20 μm or more. The upper limit of the thickness of the transparent high heat resistant film is not particularly limited, but it is preferably 200 μm or less, more preferably 150 μm or less, and further preferably 90 μm or less for use as a flexible electronic device. If it is too thin, it will be difficult to produce and transport the film, and if it is too thick, it will be difficult to transport the film.
The colorless and transparent polyimide film exhibiting the coefficient of linear expansion (CTE) of the present invention can also be realized by stretching in the film forming process of the polyimide film. In such a stretching operation, a polyimide solution is applied to a support for producing a polyimide film, dried to form a polyimide film containing 1 to 50% by mass of a solvent, and further peeled off on or from the support for producing a polyimide film. In the process of high-temperature treatment and drying of a polyimide film containing 1 to 50% by mass of solvent in the state of being in the state, 1.5 to 4.0 times in the MD direction and 1.4 to 3.0 times in the TD direction. It can be realized by stretching to. At this time, an unstretched thermoplastic polymer film is used as a support for producing a polyimide film, and the thermoplastic polymer film and the polyimide film are stretched at the same time, and then the stretched polyimide film is peeled off from the thermoplastic polymer film. In particular, it is possible to prevent scratches entering the polyimide film during stretching in the MD direction, and it is possible to obtain a high-quality, colorless and transparent polyimide film.

The average coefficient of linear expansion (CTE) between 30 ° C. and 300 ° C. of the transparent high heat resistant film is preferably 50 ppm / K or less. It is more preferably 45 ppm / K or less, further preferably 40 ppm / K or less, still more preferably 30 ppm / K or less, and particularly preferably 20 ppm / K or less. Further, it is preferably -5 ppm / K or more, more preferably -3 ppm / K or more, and further preferably 1 ppm / K or more. When the CTE is within the above range, the difference in the coefficient of linear expansion from that of a general support (inorganic substrate) can be kept small, and the transparent high heat resistant film and the inorganic substrate are peeled off or peeled off even when subjected to a heat application process. , It is possible to avoid warping together with the support. Here, CTE is a factor that represents reversible expansion and contraction with respect to temperature. The CTE of the transparent high heat resistant film refers to the average value of the CTE in the flow direction (MD direction) and the CTE in the width direction (TD direction) of the transparent high heat resistant film. The method for measuring CTE of the transparent high heat resistant film is as described in Examples.

The transparent high heat resistant film can contain a filler. The filler is not particularly limited, and examples thereof include silica, carbon, and ceramic, and silica is preferable. These fillers may be used alone or in combination of two or more. By adding the filler, protrusions are imparted to the surface of the transparent high heat resistant film, thereby increasing the slipperiness of the transparent high heat resistant film surface. Further, by adding a filler, the CTE and Rth of the transparent high heat resistant film can be suppressed to a low level. The average particle size of the filler is preferably 1 nm or more, more preferably 5 nm or more, still more preferably 10 nm or more, and particularly preferably 30 nm or more. Further, it is preferably 1 μm or less, more preferably 500 nm or less, still more preferably 100 nm or less.

It is preferable to adjust the filler content in the transparent high heat resistant film according to the average particle size of the filler. When the particle size of the filler is 30 nm or more, it is preferably 0.01 to 5% by mass, more preferably 0.02 to 3% by mass, still more preferably 0.05 to 2% by mass, and particularly. It is preferably 0.1 to 1% by mass. On the other hand, when the average particle size is less than 30 nm, it is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, still more preferably 5 to 30% by mass, and particularly preferably 10 to 20% by mass. It is mass%. By adjusting the content within the above range, the slipperiness of the surface of the transparent high heat resistant film can be kept high without impairing the transparency of the transparent high heat resistant film, and the CTE and Rth of the transparent high heat resistant film are kept low. be able to.

The method for adding the filler in the transparent high heat-resistant film is not particularly limited, but is powder when or after the above-mentioned polyamic acid (polyimide precursor) solution, polyimide solution, polyamide-imide solution, or polyamide solution is prepared. Examples thereof include a method of adding in the form of a filler / solvent (slurry), and a method of adding in a slurry is particularly preferable. The slurry is not particularly limited, but is a slurry in which silica having an average particle diameter of 10 nm is dispersed in N, N-dimethylacetamide (DMAC) at a concentration of 20% by mass (for example, Nissan Chemical Industries, Ltd. "Snowtex (registered trademark) DMAC). -ST "or a slurry in which silica having an average particle diameter of 80 nm is dispersed in N, N-dimethylacetamide (DMAC) at a concentration of 20% by mass (for example, Nissan Chemical Industries, Ltd." Snowtex (registered trademark) DMAC-ST- ZL ") and the like.

Further, when the transparent high heat resistant film has a laminated structure of two or more layers, if the difference in CTE of each layer is different, it causes warpage, which is not preferable. Therefore, the CTE difference between the first transparent high heat resistant film layer in contact with the inorganic substrate and the second transparent high heat resistant film layer adjacent to the first transparent high heat resistant film without contacting the inorganic substrate is preferable. It is 40 ppm / K or less,
It is more preferably 30 ppm / K or less, and even more preferably 15 ppm / K or less. In particular, it is preferable that the thickest layer of the second transparent high heat resistant film is within the above range. Further, it is preferable that the transparent high heat resistant film has a symmetrical structure in the film thickness direction because warpage is unlikely to occur.

The CTE of the first transparent high heat resistant film alone is preferably 20 ppm / K or less. Since the CTE difference from the inorganic substrate is small, it is more preferably 15 ppm / K or less, and further preferably 10 ppm / K or less. Although the lower limit is not limited, it is preferably −10 ppm / K or higher, more preferably −5 ppm / K or higher, and even more preferably 1 ppm / K or higher for use as a flexible electronic device. The CTE of the first transparent high heat resistant film refers to the average value of the CTE in the flow direction (MD direction) and the CTE in the width direction (TD direction) of the transparent high heat resistant film, and the measuring method is as described in Examples.

It is preferable that the first transparent high heat resistant film is transparent polyimide. When the second transparent high heat resistant film further has a plurality of laminated configurations, it is preferable that at least one layer of the second transparent high heat resistant film is transparent polyimide, and among the second transparent high heat resistant films, It is more preferable that the thickest layer is transparent polyimide. More preferably, all layers of the second transparent high heat resistant polyimide are transparent polyimide.

The first transparent high heat resistant film layer in contact with the inorganic substrate preferably contains a polyimide having the structure of the following formula 1 and / or the following formula 2. Among the first transparent high heat resistant film layers, the total amount of the polyimides having the structures of the

formulas

1 and 2 is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass. % Or more, particularly preferably 95% by mass or more, and 100% by mass or more may be used. By containing the polyimide having the structure of the formula 1 and / or the formula 2 within the above range, the first transparent high heat resistant film can express excellent CTE. Further, when the mixture between the transparent and highly heat-resistant film layers is large, or when the structure is close to a symmetrical structure in the film thickness direction, the warp of the laminated body becomes good.

The heat shrinkage of the transparent high heat resistant film between 30 ° C. and 500 ° C. is preferably ± 0.9%, more preferably ± 0.6%. The heat shrinkage rate is a factor that represents irreversible expansion and contraction with respect to temperature.

The tensile breaking strength of the transparent high heat resistant film is preferably 60 MPa or more, more preferably 120 MPa or more, and further preferably 240 MPa or more. The upper limit of the tensile breaking strength is not particularly limited, but is practically less than about 1000 MPa. When the tensile breaking strength is 60 MPa or more, it is possible to prevent the transparent high heat resistant film from breaking when peeled from the inorganic substrate. The tensile breaking strength of the transparent high heat resistant film refers to the average value of the tensile breaking strength in the flow direction (MD direction) and the tensile breaking strength in the width direction (TD direction) of the transparent high heat resistant film. The method for measuring the tensile breaking strength of the transparent high heat resistant film is as described in Examples. Even when the glass substrate was coated with the casting applicator and then manufactured, the two directions orthogonal to the casting applicator application were defined as (MD direction) and (TD direction), respectively. Hereinafter, the tensile elongation at break and the tensile elastic modulus are also the same.

The tensile elongation at break of the transparent high heat resistant film is preferably 1% or more, more preferably 5% or more, and further preferably 20% or more. When the tensile elongation at break is 1% or more, the handleability is excellent. The tensile elongation at break of the transparent high heat resistant film refers to the average value of the tensile elongation at break in the flow direction (MD direction) and the tensile elongation at break in the width direction (TD direction) of the transparent high heat resistant film. The method for measuring the tensile elongation at break of the transparent high heat resistant film is the method described in Examples.

The tensile elastic modulus of the transparent high heat resistant film is preferably 2 GPa or more, more preferably 3 GPa or more, and further preferably 4 GPa or more. When the tensile elastic modulus is 3 GPa or more, the transparent high heat-resistant film is less stretched and deformed when peeled from the inorganic substrate, and is excellent in handleability. The tensile elastic modulus is preferably 20 GPa or less, more preferably 12 GPa or less, and further preferably 10 GPa or less. When the tensile elastic modulus is 20 GPa or less, the transparent high heat resistant film can be used as a flexible film. The tensile elastic modulus of the transparent high heat resistant film refers to the average value of the tensile elastic modulus in the flow direction (MD direction) and the tensile elastic modulus in the width direction (TD direction) of the high heat resistant film. The method for measuring the tensile elastic modulus of the transparent high heat-resistant film is as described in Examples.

The thickness unevenness of the transparent high heat resistant film is preferably 20% or less, more preferably 12% or less, still more preferably 7% or less, and particularly preferably 4% or less. When the thickness spot exceeds 20%, it tends to be difficult to apply to a narrow part. The thickness unevenness of the transparent high heat-resistant film can be obtained by, for example, randomly extracting about 10 positions from the film to be measured with a contact-type film thickness meter, measuring the film thickness, and calculating based on the following formula. can.
Film thickness spots (%)
= 100 x (maximum film thickness-minimum film thickness) ÷ average film thickness

The transparent high heat resistant film is preferably obtained in the form of being wound as a long transparent high heat resistant film having a width of 300 mm or more and a length of 10 m or more at the time of its manufacture, and is a roll wound around a winding core. The one in the form of a transparent high heat resistant film is more preferable. When the transparent high heat resistant film is wound in a roll shape, it is easy to transport the transparent high heat resistant film in the form of a rolled transparent high heat resistant film.

In the transparent high heat resistant film, in order to ensure handleability and productivity, a lubricant (particle) having a particle diameter of about 10 to 1000 nm is added to the transparent high heat resistant film in an amount of about 0.03 to 3% by mass. It is preferable that the film is contained to provide fine irregularities on the surface of the transparent high heat-resistant film to ensure slipperiness.

In the transparent high heat resistant film having a laminated structure of two or more layers, in particular, the first transparent high heat resistant film layer in contact with the inorganic substrate and the second transparent high heat resistant film adjacent to the first transparent high heat resistant film layer. It is desirable that there is a mixture at the interface with the film layer (hereinafter, also simply referred to as "second transparent high heat resistant film layer"). If the thickness of the mixture is small, the transparent high heat resistant film depends on the physical properties of each layer. The thickness of the mixture is preferably more than 800 nm, more preferably 1000 nm or more, and particularly preferably 2000 nm or more, because it causes warpage and easily peels off between layers. If it is too much, it is necessary to increase the total thickness, and mixing may occur on the outermost surface of the transparent high heat resistant film, which may make it difficult to thin the film. The upper limit is caused by the limitation of the film thickness. Industrially, there is no problem if it is 5 μm or less, and preferably 3 μm or less.

The means for forming the layer having a large amount of mixing is not particularly limited, but preferably, two layers of the first transparent high heat resistant film layer and the second transparent high heat resistant film layer are applied simultaneously or sequentially (hereinafter, "" It is also called "simultaneous / sequential coating") to produce a film integrated by solution film formation while diffusing the solutions. When the next layer (second layer) is prepared (applied) after heating (drying) the first layer, the mixed layer becomes a mixture layer regardless of whether the heating process is in the middle stage or after completion. It will be less than when it is applied simultaneously and sequentially. However, even if it is heated (dried) halfway, for example, if a solution containing a large amount of solvent is applied to the second layer and the time for the solvent to diffuse is waited, the mixture will be mixed as compared with the case of simultaneous and successive application. Often there are few layers, but the mixing itself is promoted. Further, even when heated (dried) halfway, for example, if a solvent is applied on the second layer to promote the diffusion of the solvent, the number of mixed layers is often smaller than that in the case of simultaneous / successive application. However, the mixing itself is promoted.

By using a material (resin) having different physical properties as a two-layer film, it is possible to produce a film having various characteristics. Further, by laminating in a symmetrical structure in the thickness direction (for example, a first transparent high heat resistant film layer / a second transparent high heat resistant film layer / a first transparent high heat resistant film layer), the balance of CTE of the entire film is balanced. It is possible to obtain a film that is good and less likely to warp. Further, it is conceivable to make one of the layers a layer having absorption in the ultraviolet or infrared rays to give characteristics to the spectral characteristics, or to control the incident emission of light by layers having different refractive indexes.

As a means for producing a film having two or more layers, simultaneous coating with a T-die capable of simultaneously ejecting two layers, sequential coating in which one layer is applied and then the next layer is applied, and one layer is applied and then dried. There are various methods such as the method of applying the next layer after advancing the process, the method of applying the next layer after finishing the film formation of one layer, or the multi-layering by heat laminating by inserting a thermoplastic layer. Although a method can be considered, in this patent, various existing coating methods and multi-layering methods can be appropriately adopted.

The thickness of the first transparent high heat resistant film is preferably 0.1 μm or more. It is more preferably 0.4 μm or more, further preferably 1 μm or more, still more preferably 2 μm or more, and particularly preferably 3 μm or more because it is less susceptible to the influence of mixing. Further, from the viewpoint of thinning the entire transparent high heat resistant film, it is preferably 10 μm or less, more preferably 8 μm or less, and further preferably 5 μm or less.

<Inorganic substrate>
The inorganic substrate may be a plate-shaped substrate that can be used as a substrate made of an inorganic substance. For example, a glass plate, a ceramic plate, a semiconductor wafer, a metal or the like, and these glass plates and ceramic plates are used. Examples of the semiconductor wafer and the composite of the metal include those in which these are laminated, those in which they are dispersed, and those in which these fibers are contained.

Examples of the glass plate include quartz glass, high silicate glass (96% silica), soda lime glass, lead glass, aluminoborosilicate glass, borosilicate glass (Pylex (registered trademark)), borosilicate glass (non-alkali), and the like. Includes borosilicate glass (microsheet), aluminosilicate glass and the like. Among these, those having a coefficient of linear expansion of 5 ppm / K or less are desirable, and if it is a commercially available product, "Corning (registered trademark) 7059" or "Corning (registered trademark) 1737" manufactured by Corning Inc., which is a glass for liquid crystal display, "EAGLE", "AN100" manufactured by Asahi Glass, "OA10, OA11G" manufactured by Nippon Electric Glass, "AF32" manufactured by SCHOTT, etc. are desirable.

The semiconductor wafer is not particularly limited, but is limited to silicon wafer, germanium, silicon-germanium, gallium-arsenic, aluminum-gallium-indium, nitrogen-phosphorus-arsenide-antimony, SiC, InP (indium phosphide), InGaAs, GaInNAs, and the like. Wafers such as LT, LN, ZnO (zinc oxide), CdTe (cadmium telluride), and ZnSe (zinc selenide) can be mentioned. Among them, the wafer preferably used is a silicon wafer, and particularly preferably a mirror-polished silicon wafer having a size of 8 inches or more.

The metal includes single element metals such as W, Mo, Pt, Fe, Ni, and Au, alloys such as inconel, monel, mnemonic, carbon copper, Fe—Ni-based invar alloy, and superinvar alloy. Further, a multilayer metal plate formed by adding another metal layer or a ceramic layer to these metals is also included. In this case, if the overall coefficient of linear expansion (CTE) with the additional layer is low, Cu, Al, or the like is also used for the main metal layer. The metal used as the additional metal layer is limited as long as it has properties such as strong adhesion to a high heat resistant film, no diffusion, and good chemical resistance and heat resistance. Although not, Cr, Ni, TiN, Mo-containing Cu and the like are preferable examples.

The ceramic plates in the present invention include Al ₂ O ₃ , Mullite, AlN, SiC, crystallized glass, Cordierite, Spodumene, Pb-BSG + CaZrO3 + Al ₂ O ₃ , Crystallized glass + Al ₂ O ₃ , Crystallized Ca-BSG, BSG + Quartz, BSG +. Quartz, BSG + Al2O3, Pb- BSG + Al 2 O 3, Glass-ceramic, include foundation for ceramics such as Zerodur material.

It is desirable that the flat portion of the inorganic substrate is sufficiently flat. Specifically, the PV value of the surface roughness is 50 nm or less, more preferably 20 nm or less, and further preferably 5 nm or less. If it is coarser than this, the peel strength between the transparent high heat resistant film layer and the inorganic substrate may be insufficient.
The thickness of the inorganic substrate is not particularly limited, but is preferably 10 mm or less, more preferably 3 mm or less, still more preferably 1.3 mm or less, from the viewpoint of handleability. The lower limit of the thickness is not particularly limited, but is preferably 0.07 mm or more, more preferably 0.15 mm or more, still more preferably 0.3 mm or more. If it is too thin, it will be easily damaged and difficult to handle. If it is too thick, it will be heavy and difficult to handle.

<Laminated body>
The laminated body of the present invention is obtained by laminating the transparent high heat resistant film and the inorganic substrate substantially without using an adhesive. When the transparent high heat resistant film has a laminated structure of two or more layers, the first transparent high heat resistant film that comes into contact with the inorganic substrate and the first transparent high heat resistant film layer that does not come into contact with the inorganic substrate. It preferably contains an adjacent second transparent high heat resistant film layer. The second transparent high heat resistant film may further have a plurality of laminated configurations. Further, in the thickness direction of the laminate, both ends thereof are inorganic substrates (for example, inorganic substrate / first transparent high heat resistant film / second transparent high heat resistant film / first transparent high heat resistant film / inorganic substrate). It doesn't matter. In this case, the transparent high heat resistant film and the inorganic substrate at both ends substantially do not use an adhesive.

The shape of the laminated body is not particularly limited, and may be square or rectangular. It is preferably rectangular, and the length of the long side is preferably 300 mm or more, more preferably 500 mm or more, and further preferably 1000 mm or more. The upper limit is not particularly limited, but it is desirable to replace the industrially used substrate of size and material. If it is 20000 mm or less, it is sufficient, and 10,000 mm or less may be sufficient.

The laminate of the present invention has a warp amount of 400 μm or less when heated at 300 ° C. Since the heat resistance is good, it is preferably 300 μm or less, and more preferably 200 μm or less. The lower limit of the amount of warpage is not particularly limited, but industrially, 5 μm or more is sufficient, and 10 μm or more may be sufficient.

<Adhesive>
Substantially no adhesive layer is interposed between the inorganic substrate of the present invention and the transparent high heat resistant film. Here, the adhesive layer referred to in the present invention refers to a layer having a Si (silicon) component of less than 10% by mass (less than 10% by mass). Further, "substantially not used (not intervening)" means that the thickness of the adhesive layer interposed between the inorganic substrate and the transparent high heat resistant film is preferably 0.4 μm or less, more preferably 0.1 μm. It is less than or equal to, more preferably 0.05 μm or less, particularly preferably 0.03 μm or less, and most preferably 0 μm.

<Silane Coupling Agent (SCA)>
In the laminate, it is preferable to have a layer of a silane coupling agent between the transparent high heat resistant film and the inorganic substrate. In the present invention, the silane coupling agent refers to a compound containing 10% by mass or more of a Si (silicon) component. Further, it is preferable that the structure has an alkoxy group. Moreover, it is desirable that it does not contain a methyl group. By using the silane coupling agent layer, the intermediate layer between the transparent high heat resistant film and the inorganic substrate can be thinned, so there is little degassing component during heating, it is difficult to elute even in the wet process, and even if elution occurs, it remains in a trace amount. The effect comes out. The silane coupling agent preferably contains a large amount of silicon oxide component because the heat resistance is improved, and particularly preferably one having heat resistance at a temperature of about 400 ° C. The thickness of the silane coupling agent layer is preferably less than 0.2 μm. The range used as a flexible electronic device is preferably 100 nm or less (0.1 μm or less), more preferably 50 nm or less, and further preferably 10 nm. When normally produced, it is about 0.10 μm or less. Further, in a process in which it is desired to use as little silane coupling agent as possible, it can be used even at 5 nm or less. If it is 1 nm or less, the peel strength may decrease or some parts may not be attached, so that it is preferably 1 nm or more.

The silane coupling agent in the present invention is not particularly limited, but one having an amino group or an epoxy group is preferable. Specific examples of the silane coupling agent include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, and N-2- (amino). Ethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 2- (3,4-Epoxycyclohexyl) Ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilanevinyl trichlorsilane, vinyl Trimethoxysilane, vinyl triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxy Propyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3 -Acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane, 3-Chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isoxapropyltriethoxysilane, tris- (3-trimethoxysilyl) Propyl) isocyanurate, chloromethylphenetyltrimethoxysilane, chloromethyltrimethoxysilane and the like. Of these, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl)-are preferred. 3-Aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 2- (3, 4-Epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, aminophenyltrimethoxysilane, amino Examples thereof include phenetyltrimethoxysilane and aminophenylaminomethylphenetyltrimethoxysilane. When heat resistance is required in the process, it is desirable to connect Si and an amino group with an aromatic.

The peel strength between the transparent high heat resistant film and the inorganic substrate needs to be 0.3 N / cm or less. This makes it very easy to separate the transparent high heat resistant film from the inorganic substrate after the device is formed on the transparent high heat resistant film. Therefore, it is possible to manufacture a device conjugate capable of mass production, and it becomes easy to manufacture a flexible electronic device. The peel strength is preferably 0.25 N / cm or less, more preferably 0.2 N / cm or less, still more preferably 0.15 N / cm or less, and particularly preferably 0.12 N / cm or less. Is. Further, it is preferably 0.03 N / cm or more. Since the laminate does not peel off when the device is formed on the transparent high heat resistant film, it is more preferably 0.06 N / cm or more, further preferably 0.08 N / cm or more, and particularly preferably 0. It is 1 N / cm or more. The peel strength is a value of a laminated body after the transparent high heat resistant film and the inorganic substrate are bonded and then heat-treated at 100 ° C. for 10 minutes in an atmospheric atmosphere (initial peel strength). Further, it is preferable that the peel strength is within the above range even after the laminated body at the time of the initial peel strength measurement is further heat-treated at 300 ° C. for 1 hour in a nitrogen atmosphere (peeling strength after heat treatment at 300 ° C.).

The laminate of the present invention can be produced, for example, by the following procedure. At least one surface of the inorganic substrate is treated with a silane coupling agent in advance, and the surface treated with the silane coupling agent and the transparent high heat resistant film are laminated to obtain a laminated body in which both are laminated by pressure. Further, even if at least one surface of the transparent high heat resistant film is treated with a silane coupling agent in advance, the surface treated with the silane coupling agent and the inorganic substrate are overlapped, and both are laminated by pressure, a laminate can be obtained. can. When the transparent high heat resistant film has a laminated structure of two or more layers, it is preferable to superimpose the first transparent high heat resistant film on the inorganic substrate. Examples of the pressurizing method include normal pressing or laminating in the atmosphere or pressing or laminating in vacuum, but in order to obtain stable peel strength over the entire surface, a large-sized laminate (for example, for example). Laminating in the air is desirable for (more than 200 mm). On the other hand, if it is a laminated body having a small size of about 200 mm or less, pressing in vacuum is preferable. As for the degree of vacuum, a vacuum using a normal oil rotary pump is sufficient, and a vacuum of about 10 Torr or less is sufficient. The preferred pressure is 1 MPa to 20 MPa, more preferably 3 MPa to 10 MPa. If the pressure is high, the substrate may be damaged, and if the pressure is low, some parts may not adhere to each other. A high temperature of 90 ° C to 300 ° C, more preferably 100 ° C to 250 ° C may damage the film, and a low temperature may weaken the adhesion.

<Manufacturing of film with electronic device (flexible electronic device)>
When the laminate is used, a flexible electronic device can be easily manufactured by using existing equipment and processes for manufacturing electronic devices. Specifically, a flexible electronic device can be manufactured by forming an electronic device on a transparent high heat resistant film of a laminated body and peeling the transparent high heat resistant film together with the laminated body.
In the present specification, the electronic device refers to a wiring board having a single-sided, double-sided, or multi-layered structure for electrical wiring, an electronic circuit including an active element such as a transistor and a diode, and a passive device such as a resistor, a capacitor, and an inductor, and others. Sensor elements that sense pressure, temperature, light, humidity, etc., biosensor elements, light emitting elements, liquid crystal displays, electrophoretic displays, self-luminous displays and other image display elements, wireless and wired communication elements, arithmetic elements, storage elements, MEMS element, solar cell, thin film, etc.

In addition, the interposer function, which is an electrode that penetrates the polyimide, is also included in this wiring board. By roughly penetrating, the step of producing a through electrode after peeling off the inorganic substrate is largely omitted. A known method may be used to create the through hole. For example, a transparent high heat resistant film is pierced with a through hole by a UV nanolaser. Then, for example, by applying a conventional method used for a through hole in a double-sided printed wiring board or a via hole in a multi-layer printed wiring board, the through hole is filled with a conductive metal, and a wiring pattern with a metal as required is added. Is formed. In the transparent high heat resistant film, it may be attached to the inorganic substrate after opening the through electrode as described above. In some cases, a through electrode may be manufactured after the inorganic substrate and the transparent high heat resistant film are bonded together. It is possible to penetrate the transparent high heat resistant film and metallize it, but it is also possible to make a hole from one side of the transparent high heat resistant film and metallize it without penetrating the surface on the other side.

In the method for manufacturing a flexible electronic device in the present specification, a device is formed on a transparent high heat resistant film of a laminate produced by the above method, and then the transparent high heat resistant film is peeled off from the inorganic substrate.

<Peeling of transparent high heat resistant film with device from inorganic substrate>
The method of peeling the transparent high heat resistant film with the device from the inorganic substrate is not particularly limited, but the method of winding from the end with a tweezers or the like, making a cut in the transparent high heat resistant film, and attaching an adhesive tape to one side of the cut portion. A method of winding from the tape portion after the film is formed, a method of vacuum-adsorbing one side of the cut portion of the transparent high heat-resistant film and then winding from that portion, and the like can be adopted. If the cut portion of the transparent high heat-resistant film bends with a small curvature during peeling, stress will be applied to the device at that portion and the device may be destroyed. Therefore, peel it off with the curvature as large as possible. Is desirable. For example, it is desirable to wind it while winding it on a roll having a large curvature, or to use a machine having a structure in which the roll having a large curvature is located at the peeling portion.
As a method of making a cut in the transparent high heat resistant film, a method of cutting the transparent high heat resistant film with a cutting tool such as a cutting tool, a method of cutting the transparent high heat resistant film by relatively scanning a laser and a laminate, and a method of cutting the transparent high heat resistant film. There are a method of cutting a transparent high heat-resistant film by relatively scanning a water jet and a laminate, and a method of cutting a transparent high heat-resistant film while cutting a little to the glass layer with a semiconductor chip dicing device. Not limited. For example, in adopting the above-mentioned method, it is also possible to appropriately adopt a method such as superimposing ultrasonic waves on the cutting tool or adding a reciprocating motion or a vertical motion to improve the cutting performance.
Further, it is also useful to attach another reinforcing base material to the part to be peeled off in advance and peel off the entire reinforcing base material. When the flexible electronic device to be peeled off is the backplane of the display device, it is also possible to attach the front plane of the display device in advance, integrate it on an inorganic substrate, and then peel off both at the same time to obtain a flexible display device. be.

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples as long as the gist of the present invention is not exceeded.

[Production Example 1 (Production of Polyimide Solution 1)]
While introducing nitrogen gas into a reaction vessel equipped with a nitrogen introduction tube, a Dean-Stark tube and a reflux tube, a thermometer, and a stirring rod, 32.02 parts by mass of 2,2'-ditrifluoromethyl-4,4' -Diaminobiphenyl (TFMB), 230 parts by mass of N, N-dimethylacetamide (DMAc) was added to completely dissolve, followed by 44.42 parts by mass of 4,4'-(2,2-hexafluoroisopropylidene). ) Diphthalic acid dianhydride (6FDA) was added in portions as a solid, and then stirred at room temperature for 24 hours. Then, a polyamic acid solution (1) having a solid content of 25% by mass and a reduction end of 1.10 dl / g was obtained.
Next, 204 g of DMAc was added to the obtained polyamic acid solution to dilute the polyamic acid concentration to 15% by mass, and then 1.3 g of isoquinoline was added as an imidization accelerator. Then, while stirring the polyamic acid solution, 12.25 g (1.20 mol) of acetic anhydride was slowly added dropwise as an imidizing agent. Then, stirring was continued for 24 hours and a chemical imidization reaction was carried out to obtain a polyimide solution (molar ratio of TFMB / 6FDA = 1.00 / 1.00).
Next, 100 parts by mass of the obtained polyimide solution was transferred to a separable flask equipped with a stirrer and a stirrer, and the mixture was stirred at a speed of 120 rpm. Then, when 150 parts by mass of methanol was slowly added dropwise thereto, precipitation of powdery polyimide was confirmed.
Then, the contents of the separable flask were filtered off by suction filtration and washed with methanol. The polyimide powder separated by filtration was dried at 50 ° C. for 24 hours using a dryer, and then dried at 260 ° C. for another 5 hours to obtain the desired polyimide powder.
A dispersion obtained by dissolving 20 parts by mass of the obtained polyimide powder in 80 parts by mass of DMAc and dispersing colloidal silica as a lubricant in dimethylacetamide (Nissan Chemical Industry Co., Ltd. "Snowtex (registered trademark) DMAC-ST-" ZL ”) and silica (lubricant) were added so that the total amount of polymer solids in the polyimide solution was 1.4% by mass) to obtain a uniform polyimide solution 1.

[Production Example 2 (Production of Polyamic Acid Solution 2)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 32.02 parts by mass of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (TFMB) 279.9 Silica (DMAC-ST-ZL, manufactured by Nissan Chemical Industries, Ltd.) is a dispersion of N, N-dimethylacetamide (DMAc) by mass and colloidal silica dispersed in dimethylacetamide as a lubricant. Lubricants) were added to make the total amount of polymer solids in the polyamic acid solution 0.4% by mass) and completely dissolved, and then 9.81 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic acid. After adding the dianhydride (CBDA) and 15.51 parts by mass of 4,4'-oxydiphthalic acid dianhydride (ODPA) in solid form, the mixture was stirred at room temperature for 24 hours. Then, a polyamic acid solution 2 having a solid content of 17% by mass and a reducing viscosity of 3.60 dl / g was obtained (TFMB // CBDA / OPDA) in a molar ratio = 1.00 // 0.50 / 0.50).

[Production Example 3 (Production of Polyamic Acid Solution 3)]
After replacing the inside of the reaction vessel equipped with the nitrogen introduction tube, the reflux tube and the stirring rod with nitrogen, 19.86 parts by mass of 4,4'-diaminodiphenyl sulfone (4,4'-DDS), 4.97 parts by mass. A dispersion consisting of 3,3'-diaminodiphenyl sulfone (3,3'-DDS), 103.7 parts by mass of N, N-dimethylacetamide (DMAc) and colloidal silica as a lubricant dispersed in dimethylacetamide (Nissan Kagaku). Add industrial "Snowtex (registered trademark) DMAC-ST-ZL") so that silica (lubricant) becomes 0.4% by mass of the total amount of polymer solids in the polyamic acid solution) and completely dissolve. Then, 31.02 parts by mass of 4,4'-oxydiphthalic acid dianhydride (ODPA) was added separately in a solid state, and then the mixture was stirred at room temperature for 24 hours. Then, a polyamic acid solution 3 having a solid content of 35% by mass and a reduction viscosity of 0.70 dl / g was obtained (molar ratio of 4,4'-DDS / 3,3'-DDS / ODPA = 0.80 / 0.20. // 1.00).

[Production Example 4 (Production of Polyamic Acid Solution 4)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 22.73 parts by mass of 4,4'-diaminobenzanilide (DABAN) and 21.1 parts by mass of N, N-dimethyl Acetamide (DMAc) and a dispersion obtained by dispersing colloidal silica as a lubricant in dimethylacetamide (“Snowtex (registered trademark) DMAC-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) are mixed with silica (lubricant) in a polyamic acid solution. The total amount of the polymer solid content is 0.4% by mass), and the mixture is completely dissolved. Then, 19.32 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic acid dianilides (CBDA) is added as a solid. After the addition was carried out in portions as it was, the mixture was stirred at room temperature for 24 hours. Then, 173.1 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution 4 having an NV (solid content) of 10% by mass and a reduction viscosity of 3.10 dl / g (DABAN / CBDA molar ratio = 1.00 /. 0.985).

[Production Example 5 (Production of Polyamic Acid Solution 5)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 32.02 parts by mass of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (TFMB), 252.1 Silica (DMAC-ST-ZL, manufactured by Nissan Chemical Industries, Ltd.) is a dispersion of N, N-dimethylacetamide (DMAc) by mass and colloidal silica dispersed in dimethylacetamide as a lubricant. Lubricants) were added to make the total amount of polymer solids in the polyamic acid solution 0.4% by mass) and completely dissolved, and then 19.61 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic acid. The dianhydride (CBDA) was added in portions as a solid, and then stirred at room temperature for 24 hours. Then, 165.7 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution 5 having an NV of 11% and a reduction viscosity of 3.50 dl / g (TFMB / CBDA molar ratio = 1.00 / 1.00).

[Production Example 6 (Production of Polyamic Acid Solution 6)]
In a reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod, in a nitrogen atmosphere, 16.1 part by mass of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (TFMB) and N-methyl-2- 109 parts by mass of pyrrolidone and a dispersion (“Snowtex (registered trademark) DMAC-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) in which colloidal silica is dispersed in dimethylacetamide as a lubricant are mixed with silica (lubricant) in a polyamic acid solution. Addition was added so as to have a total polymer solid content of 0.4% by mass) and dissolved, and then 11.2 parts by mass of 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride (HPMDA) was added at room temperature. The mixture was added in portions as a solid, and stirred at room temperature for 12 hours. Next, 40.0 parts by mass of xylene was added as an azeotropic solvent, the temperature was raised to 180 ° C., and the reaction was carried out for 3 hours to separate the azeotropic generated water. After confirming that the outflow of water was completed, xylene was removed while raising the temperature to 190 ° C. over 1 hour to obtain a polyamic acid solution 6 (molar ratio of TFMB / HPMDA = 1.00 / 1.00). ).

[Production Example 7 (Production of Polyamide-imide Solution 7)]
17.8 parts by mass of cyclohexanetricarboxylic acid anhydride (H-TMA), 1.7 parts by mass of terephthalic acid (TPA), o-trizine diisocinate (o-trizine diisocinate) in a reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod. TODI) 26.4 parts by mass, triethylenediamine 0.15 parts by mass, and a dispersion obtained by dispersing colloidal silica as a lubricant in dimethylacetamide (Nissan Chemical Industry Co., Ltd. "Snowtex (registered trademark) DMAC-ST-ZL"). Is added so that silica (lubricant) becomes 0.4% by mass based on the total amount of polymer solids in the polyamic acid solution), dissolved in 150 parts by mass of N-methyl-2-pyrrolidone, and then stirred under a nitrogen stream. However, the reaction was carried out at 80 to 150 ° C. for 8 hours to obtain a transparent and viscous polyamideimide solution 7. The logarithmic viscosity of the obtained polyamide-imide was 0.8 dl / g (molar ratio of H-TMA / TPA // TODI = 0.90 / 0.10 / 1.00).

[Production Example 8 (Production of Polyamic Acid Solution 8)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 22.0 parts by mass of 2,2'-bis (trifluoromethyl) benzidine (TFMB) and 252.1 parts by mass of N , N-dimethylacetamide (DMAc) and a dispersion (“Snowtex (registered trademark) DMAC-ST-ZL" manufactured by Nissan Chemical Industries, Ltd.) in which colloidal silica is dispersed in dimethylacetamide as a lubricant, and silica (lubricant) is polyamide. Add so that the total amount of polymer solids in the acid solution is 0.4% by mass) and completely dissolve, then 22.0 parts by mass of 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride. After adding the substance (BPDA) in a solid state, the mixture was stirred at room temperature for 24 hours. Then, 165.7 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution 8 having a solid content (NV) of 11% by mass and a reduction viscosity of 3.5 dl / g (TFMB / BPDA molar ratio = 0.075 /). 0.069).

[Production Example 9 (Production of Polyamic Acid Solution 9)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 22.00 parts by mass of 2,2'-bis (trifluoromethyl) benzidine (TFMB) and 252.1 parts by mass of N. , N-Dimethylacetamide (DMAc) and a dispersion (“Snowtex (registered trademark) DMAC-ST-ZL" manufactured by Nissan Chemical Industries, Ltd.) obtained by dispersing colloidal silica as a lubricant in dimethylacetamide, and silica (lubricant) is polyamide. Add the total amount of polymer solids in the acid solution to 0.4% by mass) and dissolve completely, then 11.01 parts by mass of 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride. A substance (BPDA), 10.98 parts by mass of 4,4'-oxydiphthalic acid dianhydride (ODPA) was added in portions as a solid, and then stirred at room temperature for 24 hours. Then, 165.7 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution 9 having a solid content (NV) of 11% by mass and a reduction viscosity of 3.5 dl / g (molar ratio of TFMB / ODPA / BPDA = 0. 068 / 0.035 / 0.037).

[Production Example 10 (Production of Polyamic Acid Solution 10)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 33.36 parts by mass of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (TFMB), 336.31 By weight of N-methyl-2-pyrrolidone (NMP) was added and completely dissolved, followed by 9.81 parts by weight of 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA) 11.34. Parts of 3,3', 4,4'-biphenyltetracarboxylic dianhydride (BPDA) and 4.85 parts by mass of 4,4'-oxydiphthalic acid dianhydride (ODPA) are added separately in solid form. After that, the mixture was stirred at room temperature for 24 hours. Then, the polyamic acid solution 10 having a solid content of 15% by mass and a reducing viscosity of 3.50 dl / g (molar ratio of TFMB // CBDA / BPDA / ODPA = 1.00 // 0.48 / 0.37 / 0.15). Got

[Production Example 11 (Production of Polyamic Acid Solution 11)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 33.36 parts by mass of 2,2'-bis (trifluoromethyl) benzidine (TFMB) and 270.37 parts by mass of N. -Methyl-2-pyrrolidone (NMP) and a dispersion obtained by dispersing colloidal silica in dimethylacetamide ("Snowtex (registered trademark) DMAC-ST" manufactured by Nissan Chemical Industries, Ltd.) are mixed with silica as a polymer solid in a polyamic acid solution. Add to 0.14% by mass in total and completely dissolve, then 9.81 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride (CBDA), 11.34% by mass. After partial addition of 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride (BPDA) and 4.85 parts by mass of 4,4'-oxydiphthalic acid dianhydride (ODPA) in solid form. , Stirred at room temperature for 24 hours. Then, 165.7 parts by mass of DMAc was added and diluted to obtain a polyamic acid solution 11 (TFMB // CBDA / BPDA / ODPA molar ratio = 1.00 //) having a solid content of 18% by mass and a reduction viscosity of 2.7 dl / g. 0.48 / 0.37 / 0.15) was obtained.

[Production Example 12 (Production of Polyamic Acid Solution 12)]
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a reflux tube and a stirring rod with nitrogen, 33.36 parts by mass of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (TFMB), 366.31 Silica with N-methyl-2-pyrrolidone (NMP) by mass and a dispersion (“Snowtex (registered trademark) DMAC-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) in which colloidal silica is dispersed in dimethylacetamide as a lubricant. (Sluice) was added so that the total amount of polymer solids in the polyamic acid solution was 0.3% by mass and completely dissolved, and then 9.81 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic acid was added. Dianoxide (CBDA), 11.34 parts by mass of 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride (BPDA), 4.85 parts by mass of 4,4'-oxydiphthalic acid dianhydride (ODPA) was added separately in solid form, and then stirred at room temperature for 24 hours. Then, the polyamic acid solution 12 having a solid content of 15% by mass and a reducing viscosity of 3.50 dl / g (molar ratio of TFMB // CBDA / BPDA / ODPA = 1.00 // 0.48 / 0.37 / 0.15). Got

[Production Example 1] (Production of polyimide film A1)
The polyamic acid solution 4 obtained in Production Example 4 was applied to a non-slip material surface of a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) using a comma coater so that the final film thickness was 8 μm, followed by Production Example. The polyimide solution 1 obtained in 1 was applied onto the polyamic acid solution 4 with a die coater so that the final film thickness was 20 μm. This was dried at 110 ° C. for 10 minutes. The polyamic acid film that has obtained self-support after drying is peeled off from the A4100 film that has been used as a support, passed through a pin tenter having a pin sheet on which pins are arranged, and the film end is gripped by inserting it into the pins, and the film does not break. The pin sheet spacing is adjusted and transported so that unnecessary slack does not occur, and the film is heated at 200 ° C for 3 minutes, 250 ° C for 3 minutes, and 300 ° C for 6 minutes to carry out the imidization reaction. I made it progress. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 500 m of a polyimide film A1 having a width of 450 mm.

[Production Example 2] (Production of polyimide film A2)
The polyamic acid solution 4 obtained in Production Example 4 was applied to a non-slip material surface of a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) using a comma coater so that the final film thickness was 8 μm. The polyethylene terephthalate film A4100 passed through a hot air furnace, was wound up, and was dried at 100 ° C. for 10 minutes at this time. After winding this, it is set again on the comma coater side and spray-coated with N, N-dimethylacetamide (DMAc), and then the polyimide solution 1 obtained in Production Example 1 is applied onto the dried product of the polyamic acid solution 4. Was applied so that the final film thickness was 20 μm. This was dried at 100 ° C. for 10 minutes. After drying, the self-supporting polyamic acid film is peeled off from the support, passed through a pin tenter having a pin sheet on which pins are arranged, and the end of the film is inserted into the pins to grip the film so that the film does not break. The pin sheet spacing was adjusted so as not to cause unnecessary slack, and the film was transported, and heated at 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes to proceed the imidization reaction. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 500 m of a polyimide film A2 having a width of 450 mm.

[Production Example 3] (Production of polyimide film A3)
A part of the polyimide film A2 was temporarily fixed on the non-slip material surface of the polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) with an adhesive tape made of polyimide, and the start end was temporarily fixed on the start end, which was obtained in Production Example 4. The polyamic acid solution 4 was applied using a die coater so that the final film thickness was 8 μm. At this time, the polyamic acid solution 4 side of the polyimide film A2 was in contact with the polyethylene terephthalate film A4100, and the polyimide film A2 was coated on the polyimide solution 1 side. This was dried at 90 ° C. for 10 minutes. After drying, the polyethylene terephthalate film A4100 is separated from the polyethylene terephthalate film A4100 by peeling off the polyimide tape, passing it through a pin tenter having a pin sheet on which pins are arranged, and grasping the film by inserting it into the pins so that the film does not break. In addition, the pin sheet spacing was adjusted so as not to cause unnecessary slack, and the film was transported, and heated at 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes to proceed with the imidization reaction. .. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 200 m of a polyimide film A3 having a width of 400 mm.

[Production Example 4] (Production of polyimide film A4)
The polyamic acid solution 4 obtained in Production Example 4 was applied to a non-slip material surface of a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) using a comma coater so that the final film thickness was 8 μm. The polyethylene terephthalate film A4100 passed through a hot air furnace, was wound up, and was dried at 100 ° C. for 10 minutes at this time. After winding this, it was set again on the comma coater side, and subsequently, the polyimide solution 1 obtained in Production Example 1 was applied onto the dried product of the polyamic acid solution 4 so that the final film thickness was 20 μm. By extending the distance to put this in the hot air furnace, it took an extra minute to put it in the hot air furnace. This was dried at 100 ° C. for 10 minutes. After drying, the self-supporting polyamic acid film is peeled off from the support, passed through a pin tenter having a pin sheet on which pins are arranged, and the end of the film is inserted into the pins to grip the film so that the film does not break. The pin sheet spacing was adjusted so as not to cause unnecessary slack, and the film was transported, and heated at 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes to proceed the imidization reaction. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 500 m of a polyimide film A4 having a width of 450 mm.

[Production Example 5] (Production of Polyimide Film B)
The polyimide film B was obtained in the same operation as the polyimide film A1 of the production example 1 except that the polyimide solution 4 obtained in the production example 4 was changed to the polyamic acid solution 5 obtained in the production example 5.

[Production Example 6] (Production of Polyimide Film C)
The polyimide film C was obtained by the same operation as the polyimide film A1 of the production example 1 except that the polyimide solution 4 obtained in the production example 4 was changed to the polyamic acid solution 2 obtained in the production example 2.

[Production Example 7] (Production of polyimide film D1)
The polyimide solution 4 obtained in Production Example 4 was coated on a non-slip material surface of a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) by adjusting the final film thickness to 8 μm using a comma coater. Subsequently, the polyimide solution 1 obtained in Production Example 1 was applied onto the dried product of the polyamic acid solution 4 so that the final film thickness was 20 μm. Subsequently, the polyimide solution 4 obtained in Production Example 4 was coated by adjusting the final film thickness to 8 μm using a comma coater. This was dried at 90 to 100 ° C. for 10 minutes. After drying, the self-supporting polyamic acid film is peeled off from the support, passed through a pin tenter having a pin sheet on which pins are arranged, and the end of the film is inserted into the pins to grip the film so that the film does not break. The pin sheet spacing was adjusted so as not to cause unnecessary slack, and the film was transported, and heated at 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes to proceed the imidization reaction. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 500 m of a polyimide film D1 having a width of 450 mm.

[Production Example 8] (Production of polyimide film D2)
The operation is the same as that of Production Example 7 (polyimide film D1) except that the coating thickness is adjusted so that the final film thickness of the polyimide solution 1 is 12 μm and the final film thickness of the polyimide solution 4 is 2 μm. I got D2.

[Manufacturing Example 9] (Manufacturing of Polyimide Film E)
The operation was carried out in the same manner as in Production Example 1 except that the polyimide solution 1 was changed to the polyamic acid solution 2 and the polyamic acid solution 4 was changed to the polyamic acid solution 5, to obtain a polyimide film E.

[Production Example 10] (Production of Polyimide Film F)
The polyimide film F was obtained by changing the polyimide solution 1 to the polyamic acid solution 3 and operating in the same manner as in Production Example 1 except that the coating thickness was adjusted so that the final film thickness of the polyamic acid solution 4 was 7 μm. ..

[Production Example 11] (Production of Polyimide Film G)
The polyimide film G was obtained by changing the polyimide solution 1 to the polyamic acid solution 6 and operating in the same manner as in Production Example 1 except that the coating thickness was adjusted so that the final film thickness of the polyamic acid solution 4 was 7 μm. ..

[Production Example 12] (Production of polyimide film H1)
The polyimide film H1 was obtained by changing the polyimide solution 1 to the polyamic acid solution 7 and operating in the same manner as in Production Example 1 except that the coating thickness was adjusted so that the final film thickness of the polyamic acid solution 4 was 7 μm. ..

[Production Example 13] (Production of polyimide film H2)
The polyamic acid solution 4 obtained in Production Example 4 was applied to a non-slip material surface of a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) using a comma coater so that the final film thickness was 5 μm. The polyethylene terephthalate film A4100 passed through a hot air furnace, was wound up, and was dried at 100 ° C. for 10 minutes at this time. After winding this, it is set again on the comma coater side, the film is pulled out, N, N-dimethylacetamide (DMAc) is spray-coated, and then the polyimide amide solution 7 obtained in Production Example 7 is subjected to polyamic acid. It was applied onto the dried product of Solution 4 so that the final film thickness was 20 μm. This was dried at 100 ° C. for 10 minutes. After drying, the self-supporting polyamic acid film is peeled off from the support, passed through a pin tenter having a pin sheet on which pins are arranged, and the end of the film is inserted into the pins to grip the film so that the film does not break. The pin sheet spacing was adjusted so as not to cause unnecessary slack, and the film was transported, and heated at 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes to proceed the imidization reaction. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 500 m of a polyimide film H2 having a width of 450 mm.

[Production Example 14] (Production of Polyimide Film I)
The same operation as in Production Example 2 (polyimide film A2) was performed except that the polyimide solution 1 was changed to the polyamiimide solution 7, to obtain a polyimide film I.

[Production Example 15] (Production of Polyimide Film J)
A polyimide film G was obtained by operating in the same manner as in Production Example 1 (polyimide film A1) except that the polyamic acid solution 1 was changed to the polyamic acid solution 6.

[Production Example 16] (Production of Polyimide Film K)
The polyimide solution 1 obtained in Production Example 1 is applied onto a glass substrate using a casting applicator, heated from room temperature to 300 ° C. under a nitrogen atmosphere, kept at 300 ° C. for 1 hour, and thermally imidized. , A polyimide film / glass laminate was obtained. Then, the obtained laminate was immersed in water and then peeled off and dried to obtain a polyimide film K having a film thickness of 20 μm.

[Production Examples 17 to 22] (Production of Q from polyimide film L)
As shown in Table 2, the polyimide solution 1 obtained in Production Example 1 was changed to the polyamic acid solutions 2 to 6 and the polyamide-imide solution 7 of Production Examples 2 to 7, and the operation was the same as that of the polyimide film J. I got Q from L.

[Production Example 23] (Production of Polyimide Film R)
The polyamic acid solution 8 obtained in Production Example 8 was coated on a non-slip material surface of a polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) by adjusting the final film thickness to 0.5 μm using a comma coater. .. The polyethylene terephthalate film A4100 passed through a hot air furnace, was wound up, and was dried at 100 ° C. for 10 minutes at this time. After winding this, it was set again on the comma coater side, and subsequently, the polyimide solution 1 obtained in Production Example 1 was applied onto the dried product of the polyamic acid solution 8 so that the final film thickness was 15 μm. This was dried at 100 ° C. for 10 minutes. After drying, the self-supporting polyamic acid film is peeled off from the support, passed through a pin tenter having a pin sheet on which pins are arranged, and the end of the film is inserted into the pins to grip the film so that the film does not break. The pin sheet spacing was adjusted so as not to cause unnecessary slack, and the film was transported, and heated at 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes to proceed the imidization reaction. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain a polyimide film R having a width of 450 mm and a width of 500 m.

[Production Example 24] (Production of Polyimide Film S)
A polyimide film S was obtained in the same manner as in Production Example 23 except that the polyamic acid solution 8 was changed to the polyamic acid solution 9.

[Production Example 25] (Production of Polyimide Film T)
The polyamic acid solution 3 obtained in Production Example 3 was applied to the non-slip material surface of the polyethylene terephthalate film A4100 (manufactured by Toyo Spinning Co., Ltd.) using a comma coater so that the final film thickness was 20 μm, and then Production Example. The polyamic acid solution 4 obtained in 4 was applied onto the polyamic acid solution 3 by a die coater so that the final film thickness was 8 μm. This was dried at 110 ° C. for 10 minutes. The polyamic acid film that has obtained self-support after drying is peeled off from the A4100 film that has been used as a support, passed through a pin tenter having a pin sheet on which pins are arranged, and the film end is gripped by inserting it into the pins, and the film does not break. The pin sheet spacing is adjusted and transported so that unnecessary slack does not occur, and the film is heated at 200 ° C for 3 minutes, 250 ° C for 3 minutes, and 300 ° C for 6 minutes to carry out the imidization reaction. I made it progress. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain a polyimide film T having a width of 450 mm and a width of 500 m.

[Production Example 26] (Production of Polyimide Film U)
The polyamic acid solution 4 obtained in Production Example 4 was applied to the non-slip material surface of the polyethylene terephthalate film A4100 (manufactured by Toyo Spinning Co., Ltd.) using a comma coater so that the final film thickness was 4 μm, and then Production Example. The polyamic acid solution 10 obtained in No. 10 was applied onto the polyamic acid solution 4 by a die coater so that the final film thickness was 17 μm. This was dried at 110 ° C. for 10 minutes. The polyamic acid film that has obtained self-support after drying is peeled off from the A4100 film that has been used as a support, passed through a pin tenter having a pin sheet on which pins are arranged, and the film end is gripped by inserting it into the pins, and the film does not break. Adjust the pin sheet spacing so that unnecessary slack does not occur, and transport the film under the conditions of 200 ° C for 3 minutes, 250 ° C for 3 minutes, 300 ° C for 3 minutes, and 350 ° C for 3 minutes. Then, the imidization reaction was allowed to proceed. Then, the film was cooled to room temperature in 2 minutes, and the portions of the film having poor flatness were cut off with a slitter and wound into a roll to obtain 500 m of a polyimide film U having a width of 450 mm.

[Manufacturing Example 27] (Manufacturing of Polyimide Film V)
A polyimide film V was obtained in the same manner as in Production Example 26 except that the polyamic acid solution 10 was changed to the polyamic acid solution 11.

[Production Example 28] (Production of Polyimide Film W)
Made except that the polyamic acid solution 4 was changed to the polyamic acid solution 8, the polyamic acid solution 10 was changed to the polyamic acid solution 11, and the heating conditions for the imidization reaction were changed to 200 ° C. for 3 minutes, 250 ° C. for 3 minutes, and 300 ° C. for 6 minutes. A polyimide film W was obtained in the same manner as in Example 26.

[Production Example 29] (Production of Polyimide Film X)
The polyamic acid solution 10 obtained in Production Example 10 is applied onto a glass substrate using a casting applicator, heated from room temperature to 300 ° C. under a nitrogen atmosphere, and kept at 300 ° C. for 1 hour for thermal imidization. This was performed to obtain a polyimide film / glass laminate. Then, the obtained laminate was immersed in water and then peeled off and dried to obtain a polyimide film X having a film thickness of 15 μm.

[Production Example 30] (Production of Polyimide Film Y)
A polyimide film Y having a thickness of 15 μm was obtained in the same manner as in Production Example 29 except that the polyamic acid solution 10 was changed to the polyamic acid solution 11.

[Production Example 31] (Production of Polyimide Film Z)
Polyimide film Z was obtained in the same manner as in Production Example 26 except that the polyamic acid solution 4 was changed to the polyamic acid solution 12.

<Measurement of polyimide film thickness>
The thicknesses of the polyimide films A to Z were measured using a micrometer (Millitron 1245D manufactured by Fine Wolf Co., Ltd.). The results are shown in Tables 1 and 2.

<Tension elastic modulus, tensile breaking strength, and tensile breaking elongation of polyimide film>
The polyimide films A to Z were cut into strips of 100 mm × 10 mm in the flow direction (MD direction) and the width direction (TD direction), respectively, and used as test pieces. Using a tensile tester (manufactured by Shimadzu Corporation, Autograph (R) model name AG-5000A), the tensile elastic modulus and tensile fracture in each of the MD and TD directions under the conditions of a tensile speed of 50 mm / min and a chuck distance of 40 mm. The strength and tensile modulus at break were measured. The results are shown in Tables 1 and 2.

<Linear expansion coefficient (CTE) of polyimide film>
The stretch ratio of the polyimide films A to Z was measured in the flow direction (MD direction) and the width direction (TD direction) under the following conditions, and the intervals were 15 ° C. such as 30 ° C. to 45 ° C. and 45 ° C. to 60 ° C. The expansion / contraction rate / temperature was measured in, and this measurement was performed up to 300 ° C., and the average value of all the measured values was calculated as CTE. The results are shown in Tables 1 and 2.
Device name; TMA4000S manufactured by MAC Science
Sample length; 20 mm
Sample width; 2 mm
Temperature rise start temperature; 25 ° C
Temperature rise end temperature; 300 ° C
Temperature rise rate; 5 ° C / min
Atmosphere; Argon

<Polyimide film thickness direction phase difference (Rth)>
The refractive index nx in the X-axis direction, the refractive index ny in the Y-axis direction, and the refractive index nz in the Z-axis direction of the polyimide films A to Z are measured by an optical material inspection device (model RETS-100) manufactured by Otsuka Electronics Co., Ltd. It was measured with light at room temperature (20 to 25 ° C.) and a wavelength of 550 nm. After detecting the optical axis and correcting the phase advance and slow phase, the retardation measurement method was measured by the rotary photon method. Here, the X-axis and the Y-axis indicate the refractive index (nx) in the direction having the largest refractive index in the plane direction of the film and the refractive index (ny) in the vertical direction in the Nx direction in the plane direction of the film. Then, Rth was calculated from the refractive index nx in the X-axis direction, the refractive index ny in the Y-axis direction, the refractive index nz in the Z-axis direction, and the film thickness (d) based on the following equations. The results are shown in Tables 1 and 2.
Rth (nm) = | [nz- (nx + ny) / 2] x d |

<Heat shrinkage of polyimide film>
When measuring the coefficient of linear expansion (CTE) of the polyimide film, the temperature was lowered to 80 ° C after raising the temperature by 300 ° C, and the length at 100 ° C during the initial temperature rise and the length at 100 ° C during the temperature lowering. The percentage of the ratio was calculated as the coefficient of thermal shrinkage. The results are shown in Tables 1 and 2.

<Measurement of mixture between layers>
For mixing between layers, a diagonally cut surface of a polyimide film is prepared by SAICAS DN-20S type (Dipla Wintes). Next, this oblique cutting surface was measured by a microscopic IRCary 620 FTIR (Agilent) by a microscopic ATR method using a germanium crystal (incident angle 30 °). The measurement results are shown in Tables 1 and 2.

(Example 1)
The method of applying the silane coupling agent to the glass substrate was carried out using the experimental apparatus shown in FIG. FIG. 1 is a schematic view of an experimental device for applying a silane coupling agent to a glass substrate. Glass substrate 1 (OA11G glass (manufactured by NEG) having a thickness of 0.7 mm cut into a size of 100 mm × 100 mm) was used. The glass substrate 1 used was washed with pure water, dried, and then irradiated with a UV / O3 irradiator (SKR1102N-03 manufactured by LAN Technical) for 1 minute to dry wash. 150 g of 3-aminopropyltrimethoxysilane (silane coupling agent Shin-Etsu Chemical KBM903) was placed in a 1 L capacity chemical tank, and the outer water bath was heated to 41 ° C. Then, the steam that came out was sent to the chamber together with clean dry air. The gas flow rate was 25 L / min and the substrate temperature was 38 ° C. The temperature of the clean dry air was 23 ° C. and the humidity was 1.2% RH. Since the exhaust is connected to the negative pressure exhaust port, it is confirmed by the differential pressure gauge that the chamber has a negative pressure of about 10 Pa. The substrate used, the SCA coating method, and the SCA coating time of the obtained laminate are as shown in Table 3.
Next, a polyimide film A1 (70 mm × 70 mm size) was laminated on the silane coupling agent layer to obtain a laminated body. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. A laminator manufactured by MCK was used for bonding, and the bonding conditions were compressed air pressure: 0.6 MPa, temperature: 22 ° C., humidity: 55% RH, and laminating speed: 50 mm / sec. The results of measuring this laminated body are as shown in Table 3.

(Example 2)
A laminate was obtained in the same manner as in Example 1 except that the method for applying the silane coupling agent and the inorganic substrate were changed to the following. In this coating method, a Si wafer substrate (dummy grade 8-inch wafer) cut into a size of 100 mm × 100 mm was installed in a spin coater (MSC-500S manufactured by Japan Create Co., Ltd.). After dropping isopropyl alcohol (IPA) onto the glass substrate 1, rotate it at 500 rpm to spread it over the entire surface of the glass substrate, dry it, and then use a silane coupling agent 3-aminopropyltrimethoxysilane (Shinetsu Kagaku KBM903). The 1% IPA solution was dropped onto the glass and rotated at 2000 rpm to shake off and dry the silane coupling agent diluted solution. The rotation was stopped 30 seconds after the dropping. As a result, a silane coupling agent layer was formed on the glass substrate. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 3.

(Example 3)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film A2. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 3.

(Example 4)
In Example 1, the glass substrate 1 was put into the apparatus of FIG. 1 for SCA coating, but after the film A1 was tape-fixed to the glass substrate 1 in the apparatus of FIG. 1 and the SCA was applied to the film A1. The laminate was formed in the same manner as in Example 1 except that it was peeled off from the glass substrate 1 and the SCA coated surface was brought into contact with the glass side of the glass substrate 1 different from the glass used at this time and pasted. Obtained. The glass substrate used was washed with pure water, dried, and then irradiated with a UV / O3 irradiator (SKR1102N-03 manufactured by LAN Technical) for 1 minute to dry wash. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 3.

(Example 5)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film A4. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 3.

(Example 6)
The laminated surface was obtained in the same manner as in Example 2 except that the transparent high heat resistant film to be used was changed from film A1 to film B and the inorganic substrate was changed from Si wafer to glass 1. It is a polyimide surface made of a polyamic acid solution 5. As a result of measuring this laminated body, the substrate to be used and the coating method are as shown in Table 3.

(Example 7)
The transparent high heat resistant film used was changed from film A1 to film D1, and the substrate was changed from glass substrate 1 to glass substrate 2 (730 × 920 mm). Therefore, a laminate was obtained in the same manner as in Example 5 except that the silane coupling agent was applied and the laminator was changed to a large device. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 3.

(Example 8)
A laminated body was obtained in the same manner as in Example 4 except that the transparent high heat resistant film used was changed from film A2 to film D1. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 9)
A laminated body was obtained in the same manner as in Example 4 except that the transparent high heat resistant film used was changed from film A2 to film D2. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 10)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film E. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 5. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 11)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film F. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 12)
Except for changing the transparent high heat resistant film to be used from film A1 to film D1 and changing the substrate from glass substrate 1 to a Si wafer substrate (dummy grade 8-inch wafer) cut to a size of 100 mm x 100 mm. A laminate was obtained in the same manner as in Example 1. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 13)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film H1. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 14)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film H2. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 4.

(Example 15)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to R. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 8. The results of measuring this laminated body are as shown in Table 5.

(Example 16)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to S. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 8. The results of measuring this laminated body are as shown in Table 5.

(Example 17)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to T. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. The results of measuring this laminated body are as shown in Table 5.

(Example 18)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to U. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. The results of measuring this laminated body are as shown in Table 5.

(Example 19)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to V. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. The results of measuring this laminated body are as shown in Table 5.

(Example 20)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to W. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 8. The results of measuring this laminated body are as shown in Table 5.

(Example 21)
A laminated body was obtained in the same manner as in Example 1 except that the film used was changed from A1 to Z. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 12. The results of measuring this laminated body are as shown in Table 5.

(Circuit production example 1)
Each film obtained above was slit into a roll size having a width of 50 cm, and plasma-treated under the following conditions in a continuous vacuum apparatus having a winding / winding portion from the roll.
The plasma treatment conditions were a frequency of 13.56 MHz, an output of 150 W, and a gas pressure of 0.7 Pa in oxygen gas, the temperature at the time of treatment was 25 ° C., and the treatment time was 5 minutes. Next, using a nickel-chromium (15% by mass) alloy target under the conditions of a frequency of 13.56 MHz, an output of 500 W, and a gas pressure of 0.7 Pa, the thickness was increased at a rate of 10 Å / sec by an RF sputtering method under an argon atmosphere. A 120 Å nickel-chromium alloy coating (underlayer) was formed, then copper was deposited at a rate of 150 Å / sec to form a 0.25 μm thick copper thin film and wound in vacuum. In this way, a single-sided metallized film was obtained. A non-penetrating hole was made on the metal layer side of this film by adjusting the time with a nanolaser having a wavelength of 355 nm.
Using a roll-to-roll vertical continuous electroplating device, the obtained film containing non-through holes with a single-sided metal thin film was used, and a thick copper plating layer with a thickness of 3 μm (thickness) was used. An additional layer) was formed to obtain the desired metallized polyimide film. The obtained metallized polyimide film was slit to a width of 48 mm to form a sprocket hole, and then electroless plating was performed, and then double-sided through-hole plating was performed so as to have a maximum thickness of 6 μm. Then, a photoresist: FR-200 manufactured by Shipley Co., Ltd. was applied and dried, and then closely exposed with a glass photomask, and further developed with a 1.2 mass% KOH aqueous solution. Next, an etching line of cupric chloride containing HCl and hydrogen peroxide was etched at a spray pressure of 40 ° C. and 2 kgf / cm2 to prepare a transparent heat-resistant film with an electrode for connecting between films. After that, a laminate with the inorganic substrate was produced in the same manner as in the examples.

(Comparative Example 1)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film A3. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 4. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 6.

(Comparative Example 2)
A laminated body was obtained in the same manner as in Example 6 except that the transparent high heat resistant film used was changed from film A1 to film C. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 2. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 6.

(Comparative Example 3)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film I. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 2. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 6.

(Comparative Example 4)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film J. At this time, the bonded surface is a polyimide surface made of the polyamic acid solution 1. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 6.

(Comparative Example 5)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film L. At this time, the bonded surface is the surface of the polyimide surface made of the polyamic acid solution 2 that was in contact with the PET film when the film was produced. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 6.

(Comparative Example 6)
A laminated body was obtained in the same manner as in Example 1 except that the transparent high heat resistant film used was changed from film A1 to film Q. At this time, the bonded surface is the surface of the polyimide surface made of the polyamic acid solution 7 that was in contact with the PET film when the film was produced. As a result of measuring this laminated body, the substrate used, the SCA coating method, and the SCA coating time are as shown in Table 6.

<Measurement of 90 ° initial peel strength>
The laminate obtained by producing the above laminate was heat-treated at 100 ° C. for 10 minutes in an atmospheric atmosphere. Then, the 90 ° initial peel strength between the inorganic substrate (glass substrate or silicon wafer) and the polyimide film was measured. The results are shown in Tables 2 to 6.
The measurement conditions for the 90 ° initial peel strength are as follows.
Peel the film at a 90 ° angle to the inorganic substrate.
Measure 5 times and use the average value as the measured value.
Measuring device; Shimadzu Autograph AG-IS
Measurement temperature; room temperature (25 ° C)
Peeling speed; 100 mm / min
Atmosphere; Atmosphere measurement sample width; 2.5 cm

<Measurement of 90 ° peel strength after heating at 300 ° C for 1 hour>
The laminate obtained by producing the above laminate was heat-treated at 100 ° C. for 10 minutes in an atmospheric atmosphere. Further, it was heated at 300 ° C. for 1 hour in a nitrogen atmosphere. Then, the 90 ° peel strength between the inorganic substrate and the polyimide film was measured. The results are shown in Tables 2 to 6. The measurement conditions for the 90 ° peel strength after heating at 300 ° C. for 1 hour were the same as those for the 90 ° initial peel strength.

<Haze of polyimide film>
The haze of the polyimide film was measured using HAZEMETER (NDH5000, manufactured by Nippon Denshoku Co., Ltd.). A D65 lamp was used as the light source. The same measurement was performed three times, and the arithmetic mean value was adopted.
The results are shown in Tables 2-6.

<Total light transmittance of polyimide film>
The total light transmittance (TT) of the polyimide film was measured using HAZEMETER (NDH5000, manufactured by Nippon Denshoku Co., Ltd.). A D65 lamp was used as the light source. The same measurement was performed three times, and the arithmetic mean value was adopted.
The results are shown in Tables 2-6.

<Color of polyimide film>
The yellow index was measured. Using a color meter (ZE6000, manufactured by Nippon Denshoku Co., Ltd.) and a C2 light source, the tristimulus value XYZ value of the polyimide film was measured according to ASTM D1925, and the yellowness index (YI) was calculated by the following formula. The same measurement was performed three times, and the arithmetic mean value was adopted.
YI = 100 × (1.28X-1.06Z) / Y
The results are shown in Tables 2-4.

<Warp of laminated body of transparent high heat resistant film and inorganic substrate>
The warp (μm) of the laminated body of the transparent high heat-resistant film and the inorganic substrate means the degree of deformation in the thickness direction with respect to the surface direction of the laminated body before and after the following predetermined heat treatment, and specifically. As shown in FIG. 4, a 100 mm × 100 mm test piece was placed on a platen at room temperature so that the test piece was concave, and the distances from the four corner planes (h1rt, h2rt, h3rt, h4rt: unit). The average value of (mm) is taken as the original amount of warpage (mm), and after heat treatment at 300 ° C. for 1 hour, the test piece is allowed to stand on a flat surface so as to be concave, and the distances from the flat surface at the four corners (h1, h2). , H3, h4: unit mm) was defined as the warp amount (mm), and the difference from the original warp amount was defined as the warp amount at 300 ° C. The measured value shall be the average value of 10 points.
However, even if there is not enough laminate to sample 10 points, measurement is performed with 3 or more sheets. Specifically, it is calculated by the following equation.
Original warp amount (μm) = (h1rt + h2rt + h3rt + h4rt) / 4
Warpage amount (μm) = (h1 + h2 + h3 + h4) / 4
Warpage amount (μm) at 300 ° C. = Warp amount-Original warp amount The results are shown in Tables 2-6.

1 Flow meter 2 Gas inlet 3 Chemical tank (silane coupling agent tank)
4 Hot water tank (water bath)
5 Heater 6 Processing chamber (chamber)
7 Base material 8 Exhaust port 11 First transparent high heat resistant film layer 12 Second transparent high heat resistant film layer 13 Silane coupling agent layer 14 Inorganic substrate 15 Electronic device 16 Film with electronic device 17 Surface plate 18 Surface plate

Claims

In a laminate that substantially does not use an adhesive between a transparent high heat resistant film and an inorganic substrate,
A laminate in which the peel strength between the transparent high heat resistant film and the inorganic substrate is 0.3 N / cm or less, and the amount of warpage of the laminate when heated at 300 ° C. is 400 μm or less.
The transparent high heat resistant film has a laminated structure of two or more layers, and is adjacent to the first transparent high heat resistant film layer that comes into contact with the inorganic substrate and the first transparent high heat resistant film layer that does not come into contact with the inorganic substrate. The laminate according to claim 1, wherein the thickness of the mixture with the second transparent high heat-resistant film layer is more than 800 nm and 5 μm or less.
Claim 1 or 2 is characterized in that the transparent high heat resistant film has a laminated structure of two or more layers, and the CTE of the first transparent high heat resistant film layer alone in contact with the inorganic substrate is 20 ppm / K or less. The laminate described in.
The invention according to any one of claims 1 to 3, wherein the transparent high heat resistant film has a laminated structure of two or more layers, and the first transparent high heat resistant film layer in contact with the inorganic substrate is a transparent polyimide. Laminated body.
Any of claims 1 to 4, wherein the transparent high heat resistant film has a laminated structure of two or more layers, and at least one layer of the second transparent high heat resistant film layer that does not come into contact with the inorganic substrate is transparent polyimide. The laminate described in Crab.
2. The laminate described in any one.
The laminate according to any one of claims 1 to 6, wherein the long side of the inorganic substrate is 300 mm or more.
A method for producing a film with an electronic device, wherein an electronic device is formed on the transparent high heat resistant film of the laminate according to any one of claims 1 to 7, and then the electronic device is peeled off from the inorganic substrate.